Description :

This is not much about compatibility as such, but strange enough to mention (read : never saw it before);

After applying some changes in one of the (visually created) VCXes, suddenly an adjustment wouldn't save without further notice. No matter what I tried, after re-reading the method into the editor, the change had gone.

Opening the MyVCX.VCX (via Project Manager) in VFP5, and beginning to edit the class concerned, showed a "MyVCX.VCX is not an object". A rather strange message for what I intended to do I'd say.

Opening the VCX in browse showed nothing strange, and my adjustment wasn't there too.

Solution :

Not a solution of the cause, but the solution to continue, appeared to be a PACK of the VCX. Since there weren't any deleted records in there, somehow the Memo file must have got corrupted. The Pack, though, didn't say anything. It just did its work.

Remark :

It wasn't caused by opening/changeing the VCX in VFP5 or so.
After the Pack the class concerned in the VCX did normally open in VFP5 again.

Update :

Well, after quitting VFP7 once and restarting it, now all the methods of the class are gone. Something's going on here ...