The Entity Framework Model Designer doesn't work in Windows 7 RC x64. Right-clicking anywhere in the designer always shows an error dialog saying "ERROR HRESULT ...", which is dismissable, but renders the Model Designer useless.
Generating a model from a database works fine, and entities are placed on the model surface. Editing these entities is also possible. But as soon as you right-click anywhere, the error appears.
I've tried "devenv /ResetSettings" and "devenv /ResetSkipPkgs", to no avail.
(NB: I put "Vista" in the "Operating System" selection, but the problem concerns Windows 7 RC x64.)