Automatic kick in Space Jump + Network Connection Error

I've been trying to finish a Parkour game (Space jump map) for the event, but everytime I reach stage 15 (or even just a few meters before that) I get kicked from the room. I do not get any notification about it, and I have no idea how to fix it. It effectively prevents me from ever finishing that game mode.

Not only that, but curiously, I then cannot rejoin ANY other room. I automatically get Network Connection error 101 whenever I try to join a room afterwards, and this problem does not go away until I restart my PC.

Any ideas what the hell is going on?

Info: Connecting to CFNA from denmark

EDIT: Restarting Crossfire does not stop the network connection errors. I actually have to restart my PC...