Same trouble with Kubuntu 14.10 and MySQL Workbench 6.1.7
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm__CustomObject_13GridViewModel) after class_init
(mysql-workbench-bin:30405): GLib-GObject-WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm__CustomObject_13GridViewModel) after class_init
Same trouble with Kubuntu 14.10 and MySQL Workbench 6.1.7
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeModel) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragDest) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : GLib-GObject- WARNING **: attempting to add an interface (GtkTreeDragSource) to class (gtkmm_ _CustomObject_ 13GridViewModel ) after class_init
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ scroll_ to_cell: assertion 'tree_view- >priv-> model != NULL' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed
(mysql- workbench- bin:30405) : Gtk-CRITICAL **: IA__gtk_ tree_view_ set_model: assertion 'model == NULL || GTK_IS_TREE_MODEL (model)' failed