... the thing is, you can rename them into what you want, apparently ....

As long as you stick to some obvious rules, of course!
1. you have to stick to the 3 number naming convention
2. you have to rename the two accompanying info-files .part.met and its backup .part.met.bak accordingly.

For example:

example1
ren "017.part.met.bak" "105.part.met.bak"
ren "017.part.met" "105.part.met"
ren "017.part" "105.part"

example2
ren "021.part.met.bak" "106.part.met.bak"
ren "021.part" "106.part"
ren "021.part.met" "106.part.met"

example3
ren "028.part" "107.part"
ren "028.part.met" "107.part.met"
ren "028.part.met.bak" "107.part.met.bak"

Why would anyone do this? Yes, it seems a bit useless, but i was downloading a bunch of of files. Their real names had numbers in them. I wanted these number to correspond to their temp file names, so that FILE01 would be 001.part, etc.

I also used these tempfiles in another program, where it is mighty convenient that I see that the tempfiles would be aptly numbered.

So, there you have it. In short, if you wanna do this:
a. stop emule,
b. rename the files
c. re-start emule again.

If you really think about it, it would be completely useless for emule to make a fuss about this. All it should do, is care if the three files "001.part.met.bak" "001.part.met" "001.part", have the same name. There's no good reason to maintain some database, with all the names of the tempfiles, and reject them if the name is changed.

mahtoosense

Do you all agree?

Still, I'm a bit unsure whether this really works, since none of the renamed files have started downloading as of yet. But you know Emule, it's RRRRRRRREALLY excruciatingly slow, so that might not mean anything .... yet.

okay, its official: renaming the tempfiles is is absolutely possible without any adverse effect.