After clicking the “XP and later Windows Styles” button which I’d never noticed before!
OS is XP SP3 and double clicking or selecting open for these exe files does nothing at all… wxsimate is still fine.
Tried restarting and a reinstall of the upgrade package to no avail
Ouch!! I’ve never heard of this problem! However, here’s my best guess as to what might cure the problem: just find and delete (or maybe a bit safer, rename in such a way you can get them back, but they won’t be recognized) these files:
After deleting or renaming them, trying opening WXSIM, etc. again.
My understanding is that such files don’t generally exist unless they are created for some purpose (i.e. applying different styles, as is the case here), and their absence will just make the programs default to the previous appearance.