Me neither, I was just hoping that someone reading this board would know. I find that Vue 4 performance under Open GL is pretty poor - I have to have the background draw off, otherwise I get grey backgrounds in each window and the whole thing gets jerky and leaves artifacts - I have also found that the Vue slows right down if a single object with lots of polys ( eg a bank of 10-15 vue generated reeds, grouped as an object - about 600K polys) really slows down screen refresh to a crawl, and moving anything in the scene gets very jerky. Not to mention the 'lets grab all the resources on your system, and you will NOT do anything else 'til the render finishes' peculiarity, which only seems to be found on NT/2000/XP systems. I know there is a workaround for this (change the Vue.exe priority to low in the windows task manager after the render starts) Might look like a moan, but I really like the program, and accept that these are glitches that may or may not be related to my system - but that doesn't mean that I wouldn't like something done about them!