We're still trying to narrow down why certain users are having framerate issues. We've created updates on both 'next_update' and 'fastcollision' that will enable you to toggle vsync from the menu. If you are having framerate issues, try setting vsync to off and let us know what happens. Please also make sure that forced vsync is not turned on in your graphics driver settings.
added vsync option to settings menu
fixed co-op issue where player 2's energy would reset when entering a new room
fixed invisible block in the south
potential fix for crash related to dashing and swapping weapons at the same time
potential fix for rare issue where boss rush checkpoints would not be set properly