Just FYI bug 1685929 addresses adding "Mark Missing Pieces" (to the check-in page/grid) of the web staff client.
I should note however, that on the web staff it's non-trivial (probably undesirable) to open a local editor to do a Missing Pieces Letter, so likely a new task will need to be created to discuss what alternatives there are to that.
Michele,
Just FYI bug 1685929 addresses adding "Mark Missing Pieces" (to the check-in page/grid) of the web staff client.
I should note however, that on the web staff it's non-trivial (probably undesirable) to open a local editor to do a Missing Pieces Letter, so likely a new task will need to be created to discuss what alternatives there are to that.