I'm having issues with players joining my lobby to play a campaign. I have a number of mods installed to craft the campaign to my liking, and all my players have installed the mods as well. Whenever they join the loading screen says that they are downloading and installing something. I've sat there for about an hour as the load up to 100% just for the process to seem to start over? Any ideas what is going on here? I just want to play with my friends :(

Thanks in advance.