I had a lot of trouble getting it to work but I was able to get achievements to work in Crystal's Castle. I almost gave up but after scouring the interwebs for information and looking in the help file for Game Maker Studio, I figured it out. And just in time for my next game which I'm close to releasing for which I also want achievements for.
HURRAY! I got achievements working!
Source: Steam Community (opens in a new tab)
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Build 15975535 · public branch
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