Hello, I buy Decimation Map pack, but now, i dont find any game.... How many players have this downloaded content? ... 800 Microsoft points throw away

First time attempting to find a match with the DLC is always slow. It should work better after your first match. That's how it was for me when I first got it.

I would not have so much trouble with it, as I can wait a couple of minutes to get a lobby together, but there is a high chance of something happening to this lobby, either a failed host migration or that thing that happens in the pre-game lobby where you just lose everybody in the lobby, and usually results in anyone in a squad, not the squad leader, getting black screen.

It might be hard getting into a match, but staying in the same lobby for more than two games is next to impossible.