Hi Dudes!
Listen:
Ive done a Image from my Original DVD with latest Alcohol 120%
Then Ive downloaded a perfect .mds (for DPM) from copybase.ch for the EURO Version ... think there should be the US Version also.
So I was able to play the Game with DT4 (with DVD unplugged)! Good but not great...
But now Ive burned the Game and loaded it with my USB-DVD-Drive (with DVD(IDE) unplugged) ... AND IT WORKS

... its like i have my original dvd in the drive!
Hope it works 4 ya! I think you must have a absolut perfect image ... so better make one by yourself with your original dvd and use a clean .mds!
Erm by the way, please sorry my bad english (is it so bad??) ... german boy
The same with GT Legends!!
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UPDATE:
YOU HAVE TO START IT FROM PrinceOfPersia.exe NOT FROM THE CD MENU... I DONT KNOW Y BUT ONLY SO IT WORKS!!!