good job

You put a large amount of work and pretty many and good ideas into this which makes this movie a real fun watch.

However, I think you should have put some shading at the figures or at least the surroundings (especially the interior stuff).

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Wer mag schon Schnappi? Schnapsi schlägt den doch um Längen!

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Well... Some things when drawing the circle can be done easier, for example if you only mark and copy the line without the circle and then turn it 90 degrees with the "transform" window.
Apart from that, the perspective of the cube is a parallel one and not suitable for movies where a central perspective is used.
I'd rather say, tutorials should only be made by people who know flash like the back of their hand.

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Boy, that was really creepy!

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It's too small and too easy. By the way, I noticed a small bug, when the ball was behind that triangular thing.