Check my link for a temp fix for the buggy tracks - http://avalonmod.wikia.com/wiki/Thread:6404. As for the numbers after your ip address are actually ports. It is perfectly normal. Same goes for Minecraft and such. You make the initial connection in your case on port 7777 to your server. Your server then picks a random port to make the actual connection for the specific client (but only local on where the server is running). The reason for doing so is to transfer files, tile updates, player movement and so forth. Please note: Those random ports never need to be port fowarded via the router as it is only for the server itself to prevent lag.