Here is the full list of all 18 Cogs achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Earn 200 stars
Earn 100 stars
Complete 10 levels in Inventor Mode
Earn your first triple-gold award
Complete 10 Time Challenges
Complete 10 Move Challenges
Complete 50 levels in Inventor Mode
Complete 50 Time Challenges
Complete 50 Move Challenges
Earn 10 triple-gold awards
Earn 400 stars
Earn every star
Unlock every level in Inventor Mode
Earn at least bronze Time and Move awards on all music levels
Earn triple-gold on all music levels
Earn at least bronze Time and Move awards on all flying levels
Earn triple-gold on all flying levels
Finish a level in Inventor Mode in 5 seconds or less