picked a sky, created a new terrain, applied material to terrain. crashes did above plus erode, gravel and several others. clicked ok program gets fatal error and locks up and i have to force quit created sky , created terrain, did not manipulate terrain in any way. Created a tree and moved it around where i wanted it. Rendered it no problem. problems seem to be in terrain editor. Any other things i could try to narrow this down? System 10 does not use extentions so there isn't a problem there. And i have been working with open gl off the whole time. mike