I wonder if your having the dreaded 'frame 0' effect. If you make changes to almost ANYTHING in Carrara AFTER frame 0, then you've made 2 keyframes that will take your changes and distort the itme in question depending on where you are in your animation when you made the change. For example: You like what you see as you play back your animation, but there's an issue with a texture at a certain point. (The bump map doesn't seem to work, etc...) So you go to that point so your camera is looking at it to see the change, you make the change, and then you rewind to the begining, and run the animation. ARGH! Didn't I just make that change?! You stop it and make the change again. (Now your at frame 4, say...) You rewind... HEY! DIDN'T I JUST MAKE THAT CHANGE! WHAT THE &@#%^$*&@# IS WRONG WITH THIS PROGRAM!!! You make the change again... (at frame 14...) I think you see where this sad tale goes from here. You end up asking for your money back from Eovia. Your children learn some new and interesting words coming out of your computer room. And the project NEVER gets done. ;) One of the tricks to this program is ALWAYS look at your frame position before making a change! If you DO want a shader to change over time... great! If you DON'T... rewind to the correct spot (FRAME 0) and make your change. If you need to see the changes, use the Director's camera instead of you rendering camera to watch the change happen. Hope this helps!