downloading from yourself doesn't go through your ISP it goes directly from winmx to winmx (if you have a router then perhaps through that, otherwise it never leaves the computer)
try the room again, there isn't always someone there 24/7 but most of the time there is, and being evening now it's normally got someone around whereas during the day there is often fewer people there (they use excuses about "work" or something to get out of it...)
the only way to really tell is a test transfer which requires going in to the room to do it