still learning blender myself so not promising I'm dead right lol

to "snap" the rig to the mesh its just parent(select mesh hold shift an select rig then ctrl+p) dont know of a tut for poser tools but look for ones using rigify and the method is the same, bone heat works quite well but may need adjusting

never tried to make bvh in blender but when I have used it with poser the biggest problem was poser having dif bone names to most of the bvh's I had downloaded, if your using posetools then I guess the bonenames will be the same but let us know if/how it works out

had the demo of endorphin!! lot of fun init, dont think blender can do that but I haven't dived into the physics side of blender yet so will be fun to find out

hope that helps