You have a cap for how many games you can have offered or open at once, and the likely reason you're at the cap is because you haven't closed games you've been in— I see you're still in the one I played with you, for instance! =]
You can also increase the cap by spending the "Gold" you get from levels (or winning games in particular ways) to increase, which you do in the settings section. (You can also see how many open slots and gold you have by clicking on your username at the top left of any of the pages.)
Is the interface acting buggy for you? There are buttons on various different pages for all the things you seem to be having trouble with.
Edit: I also checked out what the game looked like without a script-blocker and without the Integrated Chat option on (in Settings), and the popup is a little annoying, but it has more space than the slideout style it had before, and tag buttons.
Edit2: Also, the Games list is much longer and less compact with scripts on; it seems it's not formatting the date/time of the last game action correctly due to length.