Wow, this is going to be one of *those* problems... No luck running Manager on a new machine, ditto for trying a manual tftp grab.
Seems the control unit is simply not responding to tftp requests - or not responding to the right place. I may throw the control unit and a single PC on a hub and sniff the traffic to see what's really going on. In the mean time, users are screaming for config changes. Just another fun week in IT.