The Garou will work in P4, Pro Pack, and P5.

P4 users have to convert the JPEG bump maps to Poser's BUM format by applying them manually once, but otherwise it includes MAT poses and material files for all three versions.

You can do the head morphs in 3DS Max by altering the head geometry and exporting to .obj format. As long as the vertex count and vertex order remain unchanged from the original, Poser will be able to read these modified heads as morph targets.

There's often some difficulty with 3DS Max's scale when importing/exporting meshes, but I'm not sufficiently familiar with the plugin to discuss which settings to use.