Hi,
i've got same router.
Read this
http://wl500g.info/showthread.php?t=10307
and go to the "10. TRANSMISSION (The torrent Client)"
I've done everything that howTo says.
Read also this thread:
http://wl500g.info/showthread.php?t=18317
This could help.
I've got for now problem how to get transfered files to computer, but downloading works . I could't conect to router by ftp but i think that i find solution.