Our server just transferred to your Duelers mod 1.0 and we immediately found an odd little bug. It seems to happen to the client 0 in the server when a player joins, that client 0's name and skin is changed to the connecting player. Is this bug going to be fixed, it is rather disturbing.
We have seen some curious bugs, not yet tracked down, with spectating and rejoining while another player is joining the server. This may be related.
If you could find a way to reliably reproduce this bug and then tell me -- I will definitely fix it!
Well, this happened to me twice last night. When a person attempts to join the server and they become an "unpure client", my name and skin changes to another person after I respawn. (usually after a duel). This happens to anyone in the server that is Client 0 at the time, and you can't always change your name back immediately. I hope that offers some more light.