Found the bug - it's related to updating to the newest GameMaker runtime.
Should be resolved now, after some minor changes! Your in-game version will still say "1.1.3".
Version 1.1.3a Hotfix!
Source: Steam Community (opens in a new tab)
Build and release context
Recorded Steam release date:
Within one calendar day of this post (UTC). The listed date does not establish an exact launch time.