I found this on xboxachievements.com
All credit goes to the owner of the guide: Skullfire58.
This method takes about 30 mins. if not less
Atic Atac Walkthrough
This path will work for all three characters, as it does not use any of their unique shortcuts. Make sure that when you complete the game on one character, you select New Game instead of just jumping right back in. Otherwise, the locations of certain items will be randomized.
Using this path I was able to finish with no deaths. You don't even need the Red Key. Just make sure you keep an eye on your health and rewind if you get hit to conserve as much health as possible, especially in the room with the Demon. He deals a massive amount of damage, and you'll most likely have to circle him a couple times for the door to open.
The amount of time it takes will vary as well, mainly due to the random opening/closing of the doors. I did one run in 7:06 and then another in only 5:56 simply because the doors were more cooperative that time.
(Note: There are some screens that are staircases linking the different floors, and these only have one possible door to go through other than the one you entered, so they have been omitted from this guide. You'll usually encounter them at the end of one of the numbered steps.)
U = Up
D = Down
L = Left
R = Right
1. D, L, U.
2. L, U, Fall through the Trapdoor.
3. U, L, L Past Frankenstein, D, D, Pick up the Blue Key.
4. R, R, R, D, D, Pick up the Bottle of Booze.
5. R, R (Blue Door), R, U, U, L Past the Demon, L.
7. L, U, U, L (Blue Door), L, L, U, U, R, R, Fall through the Trapdoor.
8. Pick up the Yellow Key and head through the top-left Yellow door, L, U, Place the Bottle of Booze in any corner of the room to lure Igor away from the Blue Door, then go through it. Pick up the AC Gold Key Piece.
9. D, D, R, Go through the bottom-right door, Go through the bottom-right Yellow Door, D (Blue Door), R (Yellow Door), R, D.
10. R, U, Once in the Main Room drop the AC Gold Key Piece.
11. U (Blue Door), Drop the Blue Key, L, D.
12. R, Pick up the Green Key.
13. L, L, D (Green Door), L, Ignore the Red Key, L (Yellow Door), D, L, Pick up the G Gold Key Piece.
14. R, U, R, R, U, R, U.
15. R, D, Drop the G Gold Key Piece.
16. U, L, D.
17. L, U, U, R, D (Yellow Door).
18. L, L (Green Door), L, D, D, D (Yellow Door), Pick up E Gold Key Piece.
19. U, U, U, R, R, R, U.
20. L, Move down immediately to avoid being launched into the Trapdoor, D, D, R, U.
21. R, D, Cycle your inventory until you get the E Gold Key Piece in the left inventory slot. Pick up the G Gold Key Piece and then the AC Gold Key Piece. Leave through the right ACG door.