[Morglum007]

Cracking Installshield INstallation packets can be pretty easy or almost even impossible. In this case, i see in the first CD a data1.cab and a data1.hdr files, so i suppose it is a pretty old version of the installshield engine. No data2.cab or anything else is available. That data.tag file is so suspicious, so try to open with notepad. I think you have a game with a lot of CD check on it for certain "Disc" label. There is no way to solve that without rebuilding the installation packets. You can also do that with the Installshield Developer 8.0, but will need to shield yourself with a lot of patience. Learning how Installshield works took me 6 years. Reversing installshield packets is pretty easy, know how is working is harder and control it is almost imposiible even with a lot of experience. There is a lot of calls and the way installshield works can get crazy everyone.
You should try a tool for unpacking the data.cab named i5comp and look for all the files the installer copies into your HDD. Using the "i5comp L data1.cab" call in a DOS box should give you enough info about proceeding or leaving. I suppose that version of the game do not install a lot of movie files and read them from the CDs, so a lot of identical files in name but not in size are present. In the DVD, those calls have been removed and "updated"( is supposed).
Try it and please let us know.

Good luck!