It's hard to explain but basically Vue becomes sluggish and slow when moving objects or terrains around. Yet when I first open Vue everything is smooth and I can move a terrain from point A to B smoothly; but suddenly it stops behaving like that and moving anything becomes jerky and slow. There's often a 2 second delay from me trying to move an object to the object actually moving! It happens in all 4 view ports. I have over 700mb of RAM and use 64mb for the video card; I'm using update 4.12. It doesn't matter how many objects I have in scene - it happens with just one or with many, it's not an issue of large scenes slowing things down. And turning off/on OpenGL and hardware acceleration make no difference. Any help would be appreciated JoeBlack