If you have more than 100 folders you may need to tweak the .xml file. (SR4 only) I had that problem. P5 will read any runtime you care to set up. Put a runtime on a different rive if you like. The linking process is not automatic but there are some good tuts on it. P5 from what I know does not link to LW or MAX as well as the propack links, but since I don't use those apps, who cares, eh? As for longer render times, its still way less than Bryce. And, you have the option of using the P4 render engine inside P5. There is a steep learning curve. much of the features in P5 you will not use right away. The materials room is way different from P4 materials so just get a good cup of coffee, read the tuts, and keep a stiff upper lip as you build new brain cells. I installed P5 to a new location. Do not overwrite P4PP because you will find that for some stuff, P4 is faster and more convenient. You can use your P5 files in P4 provided that you don't have dynamic hair or texture or any of the P5 special features in it. You may find that the smoothing option is a pain in the rear with imported models in P5. Once you get the hang of the firefly, you can tweak the daylights out of it for either speed or quality. Tons of options to chose from. When you load P5, load SR4 right away (before you open P5 and start to play, or at the very latest, before the "trial edition" ends in 45 days). Don't diddle with all the security crap in the install version because its a pain in the rear and it was bypassed after SR2.1.