I just wanted to chime in with more info for you to chew on:
Pismo 400 mHz, 768 Megs memory, OS X 10.2.2, 40 gb Firewire drive

With the previous version of Limewire, I had little to no problems. Occacionally I would get the "could not move to library", but that was almost always due to lack of disk space (I only recently got the FW drive). The corrupt files only seemed to occur when I did a LOT of disk/processor intensive activity concurrently. I noticed that the space available listed at the top of finder windows did not update regularly, especially when Limewire was filling it up. Therefore, I could end up with lots of "could not moves" when the disk got full. I also had to get used to the fact that 10.2 (I don't know about 10.1) gets REALLY flaky if you try to steal the last 80-90 megs of disk space from it.

I downloaded and installed the newest version two days ago. I have since then been able to download a grand total of 1 (That's O N E) file. The other 50 or so that I have tried, about 1 third of which "finished", I was never able to locate on my hard drive. I even tried doing a search for visible and invisible items, with just fragments of the filename. NOTHING. They didn't even show up in the incomplete folder... After "finishing" or while downloading. In addition, nearly 96% of the files I downloaded (or attempted to download) were reported as corrupt. With previous editions, it would continue download. Not so with this one. It claimed to continue, but the file never materialized. I can't figure out where it's saving these files!.... in previous editions, you could specify an incomplete download folder, but in this one you can't. WTF?

Does Limewire do something really assinine and wierd, like trying to fill up its available memory with data (ie, save the file "to memory" and then write to disk when that is full?... Presumably to minimize the need for constant disk access? I don't know, but this seems to be a HUGE step backward for Limewire. These new problems are inexplicable. I'm going to try removing and reinstalling. If that doesn't work, it's back to the old version.