As in the subject - I am unable to join open games.

How can I change that?

There are no “open games” to join.

You can register for ta various types of tournaments (champiosnships, monthly cups, Infinity, user tournaments) and wait for them to start.

You can also register for games in the Waiting Room and then wait for them to start.

You can also invite other players (for unrated games).

Thanks for the answer. Now I am completely confused. There must be something in this system I don't know or understand but from what I see in the waiting room - there are players waiting to start various game and variants. I would like to play against them. I can “register” my own games and they get listed beneath their entries but we do not get matched and the games do not start.

It may take some time (hours or days) for a game to start after you register.

You may see others already registered but they mahev chosen to restrict opponents (to +-100, +-200, etc) of their rating.

It's usually faster to register for a monthly cup. You'll get 4 opponents of various strength.

Or register for Infinity and you'll usually get a new game every few days.

And feel free to send me an invitation (for any game) if you can't find an opponent or you want more.

Thanks!

That explains a lot. From what I understand - this system could be a little confusing for newcommers.

I imagine people would often register an account and want to try some games straight away. When they can't play they just leave.

On the other hand that's a way to filter out people not getting the idea of long running “PBM” style gaming.