Okay, I really did not expect this to be such a stinker, sorry

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Here's more or less a walkthrough, especially focusing on the action part, as it's probably the most difficult one.
1. Create the position shown in the image.
2. Go to the red spot and wait there.
3. As soon as the chomper is on the yellow spot and turns to you, run!
4. Go through the teleporter as quickly as possible and push the box back through.
Be sure to take the lower path, as the chomper will behave differently if you take the upper one!
5. If everything works fine, the TP should now be blocked by chomper (green) and box (blue). If not, I'm really sorry, then the action part is simply too tricky.
6. Go through the TP, collect the two coins, go through TP again and collect the other two coins, push down the boxes.
7. Do as Muzo said. Push these boxes through the TP two times and then into the water to make your way to the remaining coins.
8. In the end, enter the lower TP from the right again and collect the last to coins. Don't let the chomper bite you!

9. You can push the box back through the TP to fill the water hole in the top right corner and collect the bonus coin. The other one is simply about speed.
10. Done!
I really hope the action part is not too difficult. I'm sorry if that ruined the puzzle

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Lukas.
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