If you name new dynamic group CupF you cannot recall it.
In pose room make new group "C" for example. Press "add group" and choose "CupF". Later select "CupF", press "remove all", press "delete group".
Go to cloth room. Press "edit dynamic group". In grouping tool window select new group which you created. Probably it was "CupF" either. Press "add group" and choose "C" from the list. In cloth room grouping tool add vertex instead of polygons. Name of groups have [P] adnotation.
Looks for pictures below. First show group of polygon (as on your last picture) made in pose room. Second is group of vertex - group of polygon from first pic was added and converted to vertex in cloth room.

http://www.renderosity.com/mod/forumpro/media/folder_9/file_427945.jpg
http://www.renderosity.com/mod/forumpro/media/folder_9/file_427947.jpg

If it is not clear in clothing room try to add any existing group. You should understand how it works. Anyway look either here:
http://www.poserfashion.net/tutorials.htm
The best tutorials according to me.