Limewire's cpu & ram requirements?

[Lord of the Rings]

1. I've been wondering of late, exactly what are the operating extemities of LW & what are its minimum requirements & what would be considered as average working needs in regards to cpu & ram (whether that's mean or other please detail & explain with reasons)?
2. And does LW use scratch disk space?

These questions apply to all platforms & should they be different.

I've been using LW 4.0.4 & 4.1.4 (which I heard had a memory leak.)

Using 4.0.4, I notice it uses about 80 GB ram when I haven't been searching & there's just people uplding from me. But then, 2 hrs later I noticed it was using 125-6 MB ram (wasn't dwnlding & hadn't done a search all night.) Presently I'm using Final Cut Pro (a video app) & converting to mpeg2. Whilst LW was open, FCP was using b/w 50-60% of cpu whereas LW was using 25-30%. And fcp was using 42 MB ram (even though it can potentially use over 1 GB.) It seems LW was slowing down the conversion process for fcp. (Once I shut LW down FCP utilised up to 90% of cpu.) fcp & other apps I have are potentially 'heavy' apps as far as cpu & ram needs go, yet LW seems to use a surprisingly large amount of both. Even if it's not doing much.
3. (a) Are there explanations about why? (b) Why does LW use so much cpu? (c) Has there been any improvement in the newer developments of LW?

I use mac g4 733 i.5 gb ram & os 10.3.5
I've been using LW for over 3 yrs but only updated to version 4 some mths ago.

I wouldn't mind hearing answers from people 'actually in the know'! Be that programmers or related.