You actually think changing a GUI skin has any relation to the network component of MTA server?
Check mtaserver.conf and double check, make sure that the IP is blank and the ports are right. Actually if 1.0.5 worked and 1.1 didn't then its most likely going to be your firewall thats blocking the process as 1.0.5 and 1.1 are installed in different places you need to add a new execption for the new server.