So, I just recieved the Golden God achievement along with Meat Ninja.
Yet there is something wrong here: I still need to do 4 levels, two dark The End levels and two dark Cotton Alley levels, all the other levels, including the glitch ones, are done.
And my progress seems to be calculated wrong (German, but you get the idea):
Ironically, I had the over 100% total progress issue before getting the Golden God achievement. But just now, reached the 106%, I got it.
Somehow it makes me happy of course, but I don't feel like I deserved this.
I swear, I never cheated/hacked or did anything like that whatsoever. The only thing I could assume is the new Super Meat World counting towards my total progress, even though it should be seperated (it would make sense, because I only did about 4 levels on it so far).