Jeremy, tried the new experimental branch, it goes further but still falls short of mounting folders from my WDMyCloud.

Pics 1, 2 & 3 show what happens clicking - entire network, then WDMyCloud icon in main display window, entering and then confirming password.

Debug info from Terminal for all these actions also below:

Using connect to server; AFP mode will load folders (after very brief "unable to mount folders" message appears) but it is not happy when you try later to unmount.
SSH mode still gives "connection refused by server" message.

Terminal debug info:

craiglaptop@craiglaptop-M7x0K:~$ cd build
craiglaptop@craiglaptop-M7x0K:~/build$ ./src/pantheon-files --debug
[INFO 20:04:32.340832] Application.vala:155: Files version: 0.3.0.4
[INFO 20:04:32.341391] Application.vala:157: Kernel version: 4.4.0-47-generic
[DEBUG 20:04:32.472262] [Gtk] Connecting to session manager
[INFO 20:04:32.474887] Application.vala:83: Report any issues/bugs you might find to http://bugs.launchpad.net/pantheon-files
[DEBUG 20:04:32.537553] PluginManager.vala:124: Loading plugin for /usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-filestrash.so
[DEBUG 20:04:32.606014] PluginManager.vala:151: Loaded module source: '/usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-filestrash.so'
[DEBUG 20:04:32.606245] PluginManager.vala:124: Loading plugin for /usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-filesctags.so
[DEBUG 20:04:32.646248] PluginManager.vala:151: Loaded module source: '/usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-filesctags.so'
[DEBUG 20:04:32.646462] PluginManager.vala:124: Loading plugin for /usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-files-contractor.so
[DEBUG 20:04:32.648855] PluginManager.vala:151: Loaded module source: '/usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libpantheon-files-contractor.so'
[DEBUG 20:04:32.649037] PluginManager.vala:124: Loading plugin for /usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libnetwork-places.so
[DEBUG 20:04:32.651332] PluginManager.vala:151: Loaded module source: '/usr/lib/x86_64-linux-gnu/pantheon-files/plugins/core/libnetwork-places.so'
[DEBUG 20:04:32.960286] gof-directory-async.vala:1050: Dir file:///home not in cache
[DEBUG 20:04:32.960423] >>>>create file file:///home/craiglaptop
[DEBUG 20:04:32.978728] gof-directory-async.vala:175: Preparing directory for loading
[DEBUG 20:04:32.978824] gof-directory-async.vala:209: get_file_info
[DEBUG 20:04:32.978883] gof-directory-async.vala:218: Loading info for local directory
[DEBUG 20:04:33.120106] gof-directory-async.vala:203: enclosing mount is null 4? true
[DEBUG 20:04:33.120207] gof-directory-async.vala:392: make ready
[DEBUG 20:04:33.120288] gof-directory-async.vala:550: list directory async
[DEBUG 20:04:33.120454] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.120747] plugin.vala:201: row_iter n_children 0
[DEBUG 20:04:33.120866] gof-directory-async.vala:593: Obtained file enumerator for location file:///home/craiglaptop
[DEBUG 20:04:33.124355] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.124456] plugin.vala:201: row_iter n_children 0
[DEBUG 20:04:33.245521] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.245651] >>>>create file file:///home/craiglaptop/Documents
[DEBUG 20:04:33.245976] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.246038] >>>>create file file:///home/craiglaptop/Music
[DEBUG 20:04:33.246144] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.246197] >>>>create file file:///home/craiglaptop/Pictures
[DEBUG 20:04:33.246285] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.246340] >>>>create file file:///home/craiglaptop/Videos
[DEBUG 20:04:33.246427] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.246479] >>>>create file file:///home/craiglaptop/Downloads
[DEBUG 20:04:33.247046] QuicklistHandler.vala:41: Refreshing Unity dynamic bookmarks.
[DEBUG 20:04:33.278937] gof-callwhenready.vala:77: call when ready OK - empty list
[DEBUG 20:04:33.299888] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.299994] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.306368] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.306471] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.306769] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.306844] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.307071] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307184] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.307289] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307350] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.307437] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307498] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.307583] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307645] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.307733] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307793] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.307877] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.307935] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.308027] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.308088] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.308656] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.308724] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.308873] gof-directory-async.vala:660: after loading state is GOF_DIRECTORY_ASYNC_STATE_LOADED
[DEBUG 20:04:33.313123] plugin.vala:77: CANCEL
[DEBUG 20:04:33.313403] plugin.vala:91: CTags Plugin dir file:///home/craiglaptop
[DEBUG 20:04:33.320344] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.320476] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.320657] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.320895] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.321029] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.321153] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.321218] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.321435] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.321577] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.321643] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.321740] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.321805] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.651566] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.651658] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.651775] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.651829] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.651916] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.651967] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652051] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652102] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652185] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652234] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652327] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652378] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652458] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652509] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652587] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652638] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652716] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652767] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.652844] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.652895] plugin.vala:201: row_iter n_children 0
[DEBUG 20:04:33.652971] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653022] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653102] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653155] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653235] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653326] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653405] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653456] plugin.vala:201: row_iter n_children 0
[DEBUG 20:04:33.653529] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653578] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653656] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653705] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653783] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653834] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.653912] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.653962] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.654041] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.654092] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.654620] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.658337] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.658609] plugin.vala:198: iter n_children 1
[DEBUG 20:04:33.658666] plugin.vala:201: row_iter n_children 3
[DEBUG 20:04:33.867995] gof_file_set_thumb_state file:///home/craiglaptop/build 1
[DEBUG 20:04:33.868092] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.868908] gof_file_set_thumb_state file:///home/craiglaptop/cmake 1
[DEBUG 20:04:33.868968] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.869716] gof_file_set_thumb_state file:///home/craiglaptop/data 1
[DEBUG 20:04:33.869777] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.870477] gof_file_set_thumb_state file:///home/craiglaptop/Desktop 1
[DEBUG 20:04:33.870534] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.871229] gof_file_set_thumb_state file:///home/craiglaptop/Documents 1
[DEBUG 20:04:33.871288] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.871970] gof_file_set_thumb_state file:///home/craiglaptop/Downloads 1
[DEBUG 20:04:33.872027] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.872706] gof_file_set_thumb_state file:///home/craiglaptop/Dukto 1
[DEBUG 20:04:33.872763] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.873471] gof_file_set_thumb_state file:///home/craiglaptop/filechooser-module 1
[DEBUG 20:04:33.873530] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.874209] gof_file_set_thumb_state file:///home/craiglaptop/Insync-Drive 1
[DEBUG 20:04:33.874267] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.874942] gof_file_set_thumb_state file:///home/craiglaptop/libcore 1
[DEBUG 20:04:33.874999] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.875681] gof_file_set_thumb_state file:///home/craiglaptop/libwidgets 1
[DEBUG 20:04:33.875737] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.876422] gof_file_set_thumb_state file:///home/craiglaptop/Music 1
[DEBUG 20:04:33.876478] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.877147] gof_file_set_thumb_state file:///home/craiglaptop/new 1
[DEBUG 20:04:33.877202] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.877918] gof_file_set_thumb_state file:///home/craiglaptop/pantheon-files-daemon 1
[DEBUG 20:04:33.877978] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.878654] gof_file_set_thumb_state file:///home/craiglaptop/Pictures 1
[DEBUG 20:04:33.878712] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.879387] gof_file_set_thumb_state file:///home/craiglaptop/plugins 1
[DEBUG 20:04:33.879446] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.880117] gof_file_set_thumb_state file:///home/craiglaptop/po 1
[DEBUG 20:04:33.880176] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.880838] gof_file_set_thumb_state file:///home/craiglaptop/Public 1
[DEBUG 20:04:33.880897] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.881611] gof_file_set_thumb_state file:///home/craiglaptop/src 1
[DEBUG 20:04:33.881668] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.882350] gof_file_set_thumb_state file:///home/craiglaptop/Templates 1
[DEBUG 20:04:33.882407] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.883076] gof_file_set_thumb_state file:///home/craiglaptop/Videos 1
[DEBUG 20:04:33.883131] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.883964] gof_file_set_thumb_state file:///home/craiglaptop/AUTHORS 1
[DEBUG 20:04:33.884020] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.884861] gof_file_set_thumb_state file:///home/craiglaptop/CMakeLists.txt 1
[DEBUG 20:04:33.884917] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.885779] gof_file_set_thumb_state file:///home/craiglaptop/config.h.cmake 1
[DEBUG 20:04:33.885836] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.886676] gof_file_set_thumb_state file:///home/craiglaptop/COPYING 1
[DEBUG 20:04:33.886733] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.887399] gof_file_set_thumb_state file:///home/craiglaptop/HACKING 1
[DEBUG 20:04:33.887454] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.888277] gof_file_set_thumb_state file:///home/craiglaptop/INSTALL 1
[DEBUG 20:04:33.888332] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.888992] gof_file_set_thumb_state file:///home/craiglaptop/README 1
[DEBUG 20:04:33.889046] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.889335] gof_file_set_thumb_state file:///home/craiglaptop/Untitled%201.odt 3
[DEBUG 20:04:33.889394] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.936037] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:33.936142] >>>>reuse file file:///home/craiglaptop/Untitled%201.odt
[DEBUG 20:04:33.936207] gof_file_set_thumb_state file:///home/craiglaptop/Untitled%201.odt 2
[DEBUG 20:04:33.942047] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:34.087193] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:34.087445] transparent pixel
[DEBUG 20:04:34.087969] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:36.248832] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:36.248942] transparent pixel
[DEBUG 20:04:36.249824] gof-directory-async.vala:1039: found cached dir file:///home/craiglaptop
[DEBUG 20:04:38.387198] gof-directory-async.vala:1050: Dir network:/// not in cache
[DEBUG 20:04:38.387408] >>>>create file network:///
[DEBUG 20:04:41.703908] gof-directory-async.vala:175: Preparing directory for loading
[DEBUG 20:04:41.703988] gof-directory-async.vala:209: get_file_info
[DEBUG 20:04:41.704049] gof-directory-async.vala:240: try_query_info
[DEBUG 20:04:41.704136] gof-directory-async.vala:482: Async toggle_ref_notify file:///home/craiglaptop
[DEBUG 20:04:41.704222] gof-directory-async.vala:138: Async destruct file:///home/craiglaptop
[DEBUG 20:04:41.887205] gof-directory-async.vala:264: got file info - updating
[DEBUG 20:04:41.887534] gof-directory-async.vala:266: enclosing mount is null
[DEBUG 20:04:41.887654] gof-directory-async.vala:203: enclosing mount is null 4? true
[DEBUG 20:04:41.887721] gof-directory-async.vala:392: make ready
[DEBUG 20:04:41.887799] gof-directory-async.vala:550: list directory async
[DEBUG 20:04:41.892472] gof-directory-async.vala:593: Obtained file enumerator for location network:///
[DEBUG 20:04:41.893890] >>>>create file afp://WDMyCloud-7.local/
[DEBUG 20:04:41.896941] The specified location is not mounted [code 16]
[DEBUG 20:04:41.899900] >>>>create file smb:///
[DEBUG 20:04:41.903238] The specified location is not mounted [code 16]
[DEBUG 20:04:41.907693] gof-directory-async.vala:660: after loading state is GOF_DIRECTORY_ASYNC_STATE_LOADED
[DEBUG 20:04:41.910836] plugin.vala:77: CANCEL
[DEBUG 20:04:41.910940] plugin.vala:91: CTags Plugin dir network:///
[DEBUG 20:04:41.928028] sql-schema.vala:204: schema_version is 10
[DEBUG 20:04:41.931291] sql-schema.vala:204: schema_version is 10
[DEBUG 20:04:45.234946] AbstractDirectoryView.vala:812: Guessed content type to be application/octet-stream from name - result_uncertain true
[DEBUG 20:04:45.458365] gof-directory-async.vala:1050: Dir afp://WDMyCloud-7.local/ not in cache
[DEBUG 20:04:45.458533] >>>>reuse file afp://WDMyCloud-7.local/
[DEBUG 20:04:45.466353] gof-directory-async.vala:175: Preparing directory for loading
[DEBUG 20:04:45.466437] gof-directory-async.vala:209: get_file_info
[DEBUG 20:04:45.466490] gof-directory-async.vala:350: check network
[DEBUG 20:04:45.466561] gof-directory-async.vala:358: Network is available
[DEBUG 20:04:45.466673] gof-directory-async.vala:365: Trying to connect to connectable
[DEBUG 20:04:45.470144] gof-directory-async.vala:482: Async toggle_ref_notify network:///
[DEBUG 20:04:45.470299] gof-directory-async.vala:138: Async destruct network:///
[DEBUG 20:04:45.506481] gof-directory-async.vala:368: Socketclient is connected
[DEBUG 20:04:45.506591] gof-directory-async.vala:386: Attempt to connect to afp://WDMyCloud-7.local/ succeeded
[DEBUG 20:04:45.506682] gof-directory-async.vala:240: try_query_info
[WARNING 20:04:45.510816] gof-directory-async.vala:773: query info failed, The specified location is not mounted afp://WDMyCloud-7.local/
[WARNING 20:04:45.510949] gof-directory-async.vala:269: Failed to get file info for afp://WDMyCloud-7.local/
[DEBUG 20:04:45.511011] gof-directory-async.vala:223: try query info failed - trying to mount
[DEBUG 20:04:45.511074] gof-directory-async.vala:275: mount_mountable
[DEBUG 20:04:45.515169] gof-directory-async.vala:309: mounting ....
[DEBUG 20:04:45.627173] gof-directory-async.vala:300: Asking for password
[INFO 20:04:45.792213] [Gtk] GtkDialog mapped without a transient parent. This is discouraged.
[DEBUG 20:04:52.137978] gof-directory-async.vala:305: Password dialog finished
[DEBUG 20:04:52.196052] gof-directory-async.vala:345: enclosing mount is null 2? true
[DEBUG 20:04:52.196192] gof-directory-async.vala:228: successful mount afp://WDMyCloud-7.local/
[DEBUG 20:04:52.196266] gof-directory-async.vala:240: try_query_info
[DEBUG 20:04:52.218308] gof-directory-async.vala:264: got file info - updating
[DEBUG 20:04:52.218568] gof-directory-async.vala:266: enclosing mount is null
[DEBUG 20:04:52.218698] gof-directory-async.vala:203: enclosing mount is null 4? true
[DEBUG 20:04:52.218763] gof-directory-async.vala:392: make ready
[DEBUG 20:04:52.218828] gof-directory-async.vala:660: after loading state is GOF_DIRECTORY_ASYNC_STATE_LOADING