Make sure, that you don not have any twain or relisys drivers installed. Deinstall/Remove all these files.
Shutdown system and switch off and restart before installing winsetup.exe,
follow it's instructions.
Start the diagnostics program you'll find installed now showed me the Relisys 2412/VM3530+ Scanner as the chosen scanner and ASPI as SCSI card.
It works, though the scan-window shows you options, the 1200 is not able to perform, but who cares. With me it did not work with Photoshop 4.0 but with other Software like MS Photo Editor.