Well Dave-So.....my P5 runtime (the main one) is 7.57 Gig :) All of Poser is close to 10 gig. Since the only time Poser is extremely slow for me, is when I first start it (takes forever), I don't think the size of the runtime is that significant. There was one of the Microsoft updates that was reported (and acknowledged by Microsoft) to create slow down problems on some machines. But it wasn't program specific. In terms of what has to stay in your main runtime.....any item that relys on those special "delta" folders that both DAZ and DNA use for a few of their products. I think LaRoo might be affected by it as well. They reside in the libraries folder along with your normal library folders, and are called: !DAZ, !DNA and Micro. They have to be in the main runtime and cannot be moved from that location in the libraries. So I just leave the characters that rely on them in the main runtime as well.