If your game is crashing before you even get to the start screen, it's likely your installation is corrupted. You can try these steps to get it working again:

• Verify your game cache. Right-click Rec Room in your Library, go to the Local Files tab, and click "Verify Integrity of Game Cache." Then try to launch the game.
• Reinstall. In the Local Files tab, click "Delete Local Game Content." Once the content has been deleted, reinstall Rec Room.
• Check that your video drivers are up-to-date.