Ref: Custom Games!
Well I just did the update for BTB and I does “NOT” work in CUSTOM GAMES. It will not connect to those damn Microsoft Azure Servers .WTF?? 
This is the only way I can get it work:
https://forums.halowaypoint.com/t/a-cool-way-to-get-a-custom-game-to-work-with-a-custom-mode-that-has-been-edited/490458
We need our “OWN DEDICATED SERVER SOFTWARE PERIOD!!!”
In case you haven’t seen it:
https://forums.halowaypoint.com/t/halo-infinite-update-btb-and-more-updated-jan-19/490385
From that post:
'Hey everyone - The Hotfix was deployed at 10AM PT today for Xbox and PC and included a fix for an issue with Oddball but also was hoped to address the ongoing matchmaking issues affecting Big Team Battle.
Unfortunately it looks like today’s patch did not fully resolve the BTB matchmaking problems. The team is continuing to investigate and while we believe there may be some minor improvements, matchmaking is still not working as expected.
Many people worked hard to get this fix out the door and it’s naturally very disappointing we’re not seeing the desired and expected results. We know this is an ongoing source of frustration and the team will continue to work towards a resolution.
We’ll continue to provide updates as we have them. In the meantime, we greatly appreciate your patience and understanding as we navigate this issue.
The aforementioned grants of 5 XP boosts and Challenge Swaps also went live at 10AM today. Log in any time between now and 10AM PT on Feb. 16 and they’ll be automatically added to your inventory.
Thank you and our sincere apologies that today’s update did not go as we’d hoped. More to come.’
Ya I have read it. SO? BTB was supposed to fix with this update. Guess what? It was not fix in multiplayer or in the Custom Games area where BTB is also located.
It’s annoying and it sucks, but you got to be patient with technical fixes. They can’t be fixed over night or you end up with updates like today.
I need more challenge swaps, last challenge is a BTB one
They had a team working on it since Xmas. It was fully released shortly before Xmas. It was in development for a year longer than expected. It’s still a mess.
This is anything but ok or acceptable. Patience was waiting an extra year for the game. I’m fresh out of patience as are many players.
I’ll grind to get my money’s worth out of events, but I am otherwise done with the game. BtB isn’t even that big of an issue compared to the absolutely horrible networking they’ve got going on.
What lobby size are you using to run a BTB custom game?
Did the update fix Oddball? 
There was a fix for Oddball, yes.
Meanwhile 5 weeks later…
“You were unable to connect to the fireteam”
The bane of my existence. I just wanna play some casual BTB ughhhhhhh
I see why others say this forum is toxic, if you don’t enjoy Halo Infinite then go play something else lol That is exactly what I did, like a grown adult, I said I’ll wait for this to get better. I didn’t run to the forums and cry to complete strangers who can’t help you at all. Must be all the Teens Infinite was aimed at acting like this.
This game doesn’t need any of us to keep staying relevant. IT’S FREE