... Far slower than ver. 3.5 did. Has anyone else found this problem? Or could it be that I am using parameters that I originally saved in the old version? Can anyone point me in the direction of speeding things up? All my other programs are working as normal by the way.

In my first try-out with UF4 I opened the last image I made with UF3.05. I could open it, but got errors. And when I let it re-calculate it never finished... Working with the gradient editor was no good experience because it did not respond to my slider moves instantly but with a delay...

Ahh, Amblober, I found out about the "errors" problem.. It happened to me because I didn't have the public pars downloaded into the new version. Once I'd done that, it was all OK. However, moving the gradient editor slider still does produce a delay because it seems as though this proggie is using up a lot of bites, which is daft, as my machine is more than adequate for Poser 5, for example, and is certainly of a far higher spec than is recommended on the UF site. Of course none of this was discovered when using the trial version, as I just didn't even consider trying to load anything already made in the earlier version. Don't get me wrong, I LOVE the explorer facilities etc. and if it's going to take longer, so be it, but I'm sure this shouldn't be the case?

I found that I needed to increase the maximum number of threads that it can use. It's on the 'Fractal' page of the Options dialog. Initially it had defaulted to 4, which was making UF4 run about 33% slower than UF3 on my machine. When I increased it (to 32) UF4 ran slightly faster than UF3.

Thanks so much SimonKane.. That has made quite a difference! (What are these threads by the way?)

I am still having a problem with the gradient window. When I use the slider with non-direct colorings, it is running like the UF3 one did with direct colorings...ie, very slowly and then suddenly 'catching up'. It's kind of disconcerting when you are used to a smooth flow. Is anyone else having this problem? or maybe can suggest a fix?

'Very slowly and then catching up' - have you tried increasing the number of threads? That sounds like the sort of behaviour I would expect from a small number of threads. To explain this 'threads' thing: Windows splits the processor's time between all the programs running on the computer. Each program (or 'process') can split itself into several 'threads', each of which gets allocated time by Windows. The effect is that several things in your program (in this case UF) appear to be happening simultaneously. The maximum-threads option determines how many separate threads at a time UF can have running for a fractal window; so if you have a small limit, you'll see that only a few layers in a many-layered image appear to be progressing at a time. I don't know exactly how UF splits all its tasks into threads, so I can't be sure that increasing them will fix the gradient window problem, but it's worth a try.

As soon as I saw your reply above about the threads, I did exactly as you described, and it did run faster in other aspects, but it still lags in the gradient. Thanks for the explanation!