I saw your previous comment about the resolution and wanted to just cover this. To make it work in Godot you need to keep your sprites the correct size and then set your window in the editor settings to 64x64. You can then override the window setting (you will have to check the advanced settings button) to make it 640 x 640. I think there is also a pixel snap setting you want to enable to avoid any little pixel glitches. But...
This game is really really good. The mechanics are smooth and well realised and I had a blast chucking my corpse around to give me places to stand. I don't know how the rules will come down on whether this will count but for me at least you didn't use the extra resolution for any game mechanic so this still fits. Godot is a great engine that I use myself but setting it up for scaled pixels is not as obvious if you haven't used it much. Another tip if you update it, the camera smoothing actually hurts the rendering at the lower resolution because it's more pixels jittering around, so if you downscale it I would switch that off, that way the player stays nice and cleanly displayed in the centre.