I'm pretty sure, but I want to be 100% sure before I make an order.
Does the GPO work with DP4 without Kontakt?
Is there any known problems with DP4 and AU version?
GPO works extremely well with DP4 provided you have a sufficiently fast computer (I would say realistically 1 GHz G4 or better to run multiple instances of GPO) and plenty of RAM. Because GPO is entirely RAM-based, no disk streaming, I suggest 1.5 to 2 GB of RAM and you'll be in good shape. Gary has posted some tutuorials I wrote for DP4: