Marching Squares Autotiling in fusion - new platformer/level editor project

After some butting my head against the wall I've finally managed to get Marching Squares autotiling implemented in Fusion. Using a standard 15 image tileset, I can paint my platforms in realtime rather than changing all those background images.
15 16x16pixels images where used, so the tiling is there, but that should be easy to resolve by adding texture variation with a second image set. Same with the apparent squared edges. They'll be easy to fix.
This
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comes from this sliced into a tileset
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and applied in fusion.
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In real-time it looks like this.
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The pauses are screen capture delays. The actual process runs smoothly at 240 fps.