It’s funny but I was planning on doing a predator type mod as well but reason I didn’t was I couldn’t find any free and good meshes to use for the creatures and for the predator weapons. For replacing the skin all you have to do, I believe, is export the skeleton you want to use. Then using lets say Maya, import skeleton and the 3D mesh you want to use, such as predator, and match it with the skeleton bones. Of course you will have to remove the old mesh that is probably attached to the skeleton. There is a link somewhere on the forum that show how to do this with the hatchet, basically it is the same process but he goes into more details. However, he doesn’t go into details about character animations, he mentions about a paint tool and flooding the model but when you use a character you will have to paint different areas of the model to get it to work good, you can always see what is being used by checking out the areas that were painted on old mesh be fore you delete it. Hope I am not confusing you but hopefully if you see the vid it will make more sense. Its in one of the tutorial discussion posts. I am actually doing this for a new armor for one of my mods.