what you were downloading if it was an 800Mb file, but anyway..................
1. When you say the network only works in the next room do you mean in addition to the room the computers are in?
2. Which operating systems are the machines running?
3. Do you have a firewall on both machines, or on either of them?
4. Presumably your network is configured as an ad hoc wireless network, and not an infrastructure type?
5. Do you disconnect from the university network when transferring files?
6. Does the slowness apply both ways, i.e. laptop to PC and PC to laptop, or only in one direction?