I start the bitcomet and it be Ok, but…
Every time i start a download, the LAN STOP to work. The computers go to inacessible.
I try to find the solution;
Remove the Windows Firewall - don´t work.
Stopping the DHT - don´t work
Change the configurations of BitComet - don´t wok
Sometimes the LAN work a little time before go down. I got here 8 computers in a 3com 812 router and a hub.
What are the modem & hub models? Also, have you limited your upload speed in BitComet?
Do you have Panda Antivirus installed on any of the 8 pc’s?
This is not off-topic! 
The upload speed is limited to 30kbps, sometimes to 15kbps. My conection is 512Kbps for Download and 256kbps for Upload.
The modem is 3COM Router 812. Hub is a cheap Encore.
I got the NOD32 instaled in all machines. Panda is not compatible with NOD32 and i don´t have it.
Thanks!
(i try to acess this forum this days, but the forum was down for me)
When i was using some old version of BitComet in another computer in the same Workgroup, the BitComet was OK. Work Fine.. not too fast like this 0.70 but, work fine! I think was the 0.60 version or 0.58.
This is going more confused? 
Thanks a lot!