I wanted to make a Topic to make easier to find people interested in playing challenge mode.
If you are interested in playing cmode you can follow this topic.
When someone wants to start a party or just to look for people to play cmode can just post in this topic to send a notification to people that might be intersted to play.
Hope this will help.
I also made a cmode team, if you make an account dedicated to cmode you can join it if you want.