Put two entity types on a diagram, select the subtype connector tool. The subtype cursor is shown. Click on one entity type, drag out to the other (the subtype connector arc is shown). When the mouse passes into the 2nd entity typem the background greys to indicate the drop zone. Release the mouse, and the cursor, arc, and grey background vanish, but no subtype arrow appears. There appears to be no way to define a subtype.
I'm running Windows XP SP2 with NORMA 2007-06b CTP under Parallels Desktop 26 Feb 2007 (build 3186) on Mac OS/X. It seems to be the same whether Parallel is in full-screen, windowed or Coherence mode.
The same thing happened with the previous (May?) CTP I had previously, but I didn't worry because I assumed it would be fixed with the new CTP.
This is a pretty embarrassing bug guys - in front of a client trying to do some real-world modeling, to find the tool lets me down and I can't make any forward progress. Please let me know another way to define s subtype with this CTP.