If you integrate it in a dashboard then I dont see why you would have ram issues. And even if there are RAM issues, you could remove the follow:
Chatroom (elimitates Storing of Users Name, Shared Size, etc)
Total Shared (from all connected hubs)
Total # of Users Connected
If you do use Multi-Source Downloads, then you will need a shitload of RAM depending on the # of sources you have per download. Again to elimiate this issue I would probably just create a file for each download to manage information (Part#, Offset, Length).
But I guess it would really be a bitch to make the interface, but I guess you know how.

Ight man, good idea, but if you need any help w/ protocol let me know.
BTW: I've developed a DC Client before.
BlueCELL