We've released a quick hotfix for Steam that solves the following issues.

• Removed the option for offline play from the game. Private games are functionally equivalent in a peer-to-peer world. (If you want to play by yourself and not invite friends into your game, please set your Steam status to Offline or Invisible for the time being.)
  
• The Weekly Challenges work again.
  
• Rich Presence on Steam more accurately reflects party composition and game state. It's more reliable too.
  
• The First Time Player screen won't prevent you from entering the main menu anymore.
  
• The list of available game modes is stored locally now, so you can switch between them.
  
• Various small fixes (typos, graphical inconsistencies, etc)
  

If you're on the Xbox or Microsoft Store side and still having problems, we have multiple people dedicated to solving those issues, and hope to have an update in certification soon. We keep fixing one problem and finding two more, so it's taking longer than we hoped. Rest assured that we're really sorry it's taking as long as it is, and we're working as fast as we can to fix the problems. So you know, the issues that are showing up here in Steam will also be part of the next patch for the Microsoft platforms, as soon as we can release it.