Click on the game, and enter its contents page. Then from there, click on the little gear in the top right. Next click on the properties. This will open up the game's properties where you can then proceed.





After you've opened the properties menu, go to the "Betas" tab and then select the version titled "staging - Next Version". This is, from what I can gather, an updated version of the standard game. Which has fixed most of the bugs that were experienced. This means it should correct the achievements not unlocking bug.






Then you can play the game and unlock all of those wonderful achievements!

Or don't... that's okay too.