I agreed with MAXseer, some game engines can't handle models made of high poly count. On the other hand The main geometry of poser characters (the standard ones) belongs to Curious Labs and I guess it could be a copyright violation to use them into any game engine, If the Geometry are for DAZ models there is the same restrictions. If you have Maya, Lightwave or 3DS Max the must easier game engine from my point of view is Virtools 2.1 I like 3D game studio too.

SAL9000 - Hello Dr. Chandra, Will I've dream?