Hello,
to Timber: yes, it seems to work without compat mode. I noticed that many progs which still needed the compat. mode in Windows Vista don't need it anymore on Windows 7. Seems that M$ has done a pretty good job here.
The only thing that could happen is, that since you have that damn VirtualStore since Vista and no enough rights to write to HKLM in the registry, some progs might behave strangely, as the installer of the avalanche mod did. Starting FF7Config with admin rights fixed that problem, too. No need for compat. mode.
To Covarr: I have double checked this. As soon as your installer has run, the compat. flag for Windows 98/Me is set to "FF7.exe". Uninstalling seems to revert that change. The crash happens in "rundll32.exe" because of the shim dll (which is used by M$ for the compat. mode). Antivirus and/or M$ EMET could play a role, though. But even by completely disabling DEP in EMET, I got that BEX crash when compat. mode was set to Win 98/Me.
BTW.: I'd like to thank you all for your great work. Currently I'm playing FF7 again after MANY years with my 14 years old son. He is absolutely blown away by the great storyline. Without your awesome work this would not have been possible, or at least not in this pleasant way!
Edit: many typo's.