It is possible to use the propertygrid to designate the reference value of 0..1 relationships (selection from a dropdown), but is it possible to added ModelElements to the many end of the relationship using a CollectionEditor?

Currently the Many end doesnt actually show up in the propertygrid (as I believe its expected to be manipulated via drag and drop through the designer), but if one didnt wish to have a graphical representation for this, could it be done purely through the PropertyGrid?

An example of the desired behavior is SQL Server Enterprise Manager, designing the table.

You can add Fields to a Table through the 'designer', but Foreign Keys are added through a dialog (eg, CollectionEditor), as they have no graphical representation, otherwise they would clutter the UI.

Any tips?

Thanks!

Yes, it could be done through the property grid if you wanted to write your own TypeConverter, UITypeEditor and customize our PropertyDescriptor.