Braid: Definition of Completion

Warning: The following may contain spoilers (depending on how you define spoilers).

Braid has twelve achievements, as follows;

• Traversed World 2
  
• Traversed World 3
  
• Traversed World 4
  
• Traversed World 5
  
• Traversed World 6
  
• Completed World 2
  
• Completed World 3
  
• Completed World 4
  
• Completed World 5
  
• Completed World 6
  
• Closure (Complete the Game)
  
• Speed Run

After playing for 8.3 hours, I've done 8 of those - everything except traversing and completing World 6, finishing the game and the speed run. I also have four out of eight stars, one of which is the damned two-hour cloud one (which is why it's taken me over eight hours). I aim to get all eight stars and at least eleven of those achievements. The Speed Run, I'll leave till last, and may not complete, mostly because I'm clumsy at the best of times.