Here's how I deployed it using Group Policy:
Created an Administrative install on the server by running setup /a (it copies disk 1 and 2)
Copied the cd2run.exe file from disk 2 to the folder containing the 'mappoint' and 'pstreets' folder (if you don't do this, it asks for the Run CD when you run the deployed program, even if you do a full install).
Edited the MSI and added the Installshield Scripting redistributable using Installshield (see http://support.installshield.com/kb/view.asp?articleid=Q107978)
Set the INSTALLLEVEL=500 for a Full install
You can also use the Office Resource Kit to create transforms.