I don't remember the exact message but it was something about "not being able to write the part file in the temp directory"
I went to my temp directory and confirmed that I was not able to write. I rebooted the system, retrieved my rights and everything works fine now.
So It's probably not Amule related.
I should have read the log before posting
If I encounter another problem, I'll try to solve it myself and if I need to post, be more specific
Thank you Kry for asking.
And again congratulations for the good work. I'm using Amule since the beginning (and before since Lmule days) but I must say that since the 2.0 final release I noticed that the downloading performance improved a lot.