Well, it should have worked for you. If you download the file, look in the C:\Program Files\Microsoft ActiveSync\Microsoft Pocket Streets 2001 folder and look for the file titled: PckSts.HPC_mips.CAB
Copy that one to your 790 and tap on it...it should install and run fine.
2002 Review here:
http://www.hpcfactor.com/reviews/software/microsoft/pocketstreets-02/