An Intel based MAC running Windows XP is just another computer like a Dell or an HP. Adagio will run fine.

If the "custom designed" program is running on MAC OS X, then you will need to make sure that the file it creates is still visible when the Mac is re-booted to run under Windows (sometimes the two file systems are not visible to each other).

To make sure that the import is possible, take the file being created and have your Business Partner test the file with their copy of Adagio. The evaluation versions do not support importing data.