Clueless loss

[Ken Norris (dialup)]

I have a stack called RevExp1.rev.

It had some card graphics and an image that was grouped and a few buttons.

I have opened this stack from the Rev UI a dozen times (or more) with no
problem.

Suddenly today, I opened the stack and the graphic was gone, the image is
gone (so the group can't show it), and I cannot access the stack properties
dialog anymore (always grayed out/disabled in the menu).

The Application Overview shows the groups and the image files exist
(although they had been imported to the stack).

I have no clue what's going on. Can some one help?

Ken N.