Made it myself, I deletet the in debian the udp port and changed maxupload speed to 200 kb

I tried to play with my friend on a root server but after 6/19mb stop downloading and the downloadrate drops to 0kb/s (I can connect without any problems).

this is what the server window shows me when he connects,

1235.595 ConnectionRequestReplyConfirm (type(ConnectionRequestReplyConfirm) ) from ...