Here's one MAT thing that confused the heck out of me at first. Some MAT Pose files have MATS that should only be used with Poser Pro. If you use them with Poser, you get a black face! You can tell which is which. Look at the screenshot. You see some one that says M2Map2P4. That is used with Poser. M2Map2 is used with Poser Pro. You don't always see both options. When you do, use the P4 MATS with Poser 4. Does this make sense? If you only have Poser 4, and don't plan on getting Poser Pro, you can safely delete the Poser Pro MATS.