Here is the full list of all 367 GooCubelets achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Finish level 1 more time
Fall to your death 1 more time
Beat Level 45
Beat Level 35
Beat Level 40
Beat Level 25
Beat Level 30
Beat Level 15
Beat Level 20
Beat Level 10
Beat Level 5
Beat Level 1
Beat Level 50