I have found that trying to gather people for a custom game is very difficult. People will often leave before a game even starts. I have tried posting on the “playing soon” thread and try to get some bigger parties but of the three times I’ve tried it I haven’t gotten even one join in. Dose the thread even work? Are there other threads or discussions I can post to for some players?
What I usually do is play invasion for about 4 or 5 games beforehand. Then I invite my recent players and online friends, typically getting a group of at least 11. If all else fails, send me a FR and I'll invite you to my lobbies.
Try joining other people's games or talking to people in the chatbox. If you have a few people, ask them to invite recent players but be sure not to wait too long in the custom games lobby. You can always just start a game to keep people happy and sit afk in a corner inviting more people.
Frankly, I don't think customs have quite taken off, yet. I think more people are still more interested in playing Matchmaking and Firefight and familiarizing themself with the gameplay.
For some reason just because blops released after reach, people seemed to forget about reach when they started playing blops. That and the lack of credits for custom games seems to have diverted everyone's attention from playing custom games in Reach. Also if you haven't done so yet, fill up your friends list with people who you've played customs with and who are almost always online. That way you can join customs whenever you feel like it.
Almost all my Friends are guys i met in MM and they never like my Customs. They only want it to be on Forge World. When i invite 17 friends, only 2 of them join since most of my friends like to play unbalanced zombie games and instantly boot me if i am the MVP since they just can't stand it that they get raped over and over in their own unbalanced game. Then don't give humans unlimited fuel rods dumbass!
You could friends request me. i try to be on every week end playing with people and try to give everyone who wants to a chance to do their custom games too.
That's why you send friend requests to people on Forge Hub. We tend to have time to play customs, and lots of not unbalanced custom maps and gametypes. I happen to have space on my friends list currently...