I've tried restarting the app, restarting my computer, reinstalling the app, but nothing. it doesn't show the room list, it doesn't let me connect directly to a room.
It has been like this for more than half a year for me as well and it's disapointing that they haven't fixed it. I deleted it a while ago and FlockMod recently came up amongst my friends. It almost seems like FlockMod is ignoring the issue.
First uninstall adobe air. After that, go here https://helpx.adobe.com/air/kb/archived-air-sdk-version.html and download an older version of adobe air. Scroll down until you find "Adobe AIR 18 runtime downloads" and try this one. It should work after that.