Thanks yonnie, but that only gave me the same options as in the menu.
However, there must have been some sort of glitch in my system, as today, instead of an empty window under "installed application", I am now getting the full menu as I expected. (I've not changed the installation). On a couple of occasions the pop-up full menu you get when clicking on the PC button also disappeared - all I got was Run and Logout. It came back on a reboot. Something funny is going on, if I can reproduce it reliably I'll report back.