well the corp changes are included in a few places:
the civ4corporationinfo XML file in GameInfo contains most of the corp changes. Units and buildings also was altered for guildsmen/executives and corp wonder changes. Techs were changed as well. Text changes for the corps are in the Civ4gametext_RFCBTS. I also had to edit the globaldefines to allow more than 12 resources per corp. Map changes are of course in the map file. That's all I can remember.
The download link appears to be dead for this mod...
fixed, it's back up.
I have more changes made to my personal version but with the new patch coming out I'm waiting until afterwards to implement it.