All bugs are replicated in the attached example levels.
When you throw a SMB2-Mushroom-Blcok (npc-154/155/156/157) into a claw and wait below it for the block to drop, it kills you instantly, even if you are big Mario.
But normally, when you just throw such a block up and it falls down on you, it ignores Mario completely.
When you use a Pipe-Warp with Screen Effect set to Scroll Effect, every npc that Mario is holding (has grabbed) while warping does still interact with other npcs in level AND even with Mario, like e.g. shells killing other shells or bombs exploding and hurting Mario.
Don't know if this one is really a bug, but it's at least an unintuitive behaviour.
So in my example, kicking the green shell from Marios (Big Mario only) standpoint off should reach the red shell. But the block in the air reflects it back. Seems a bit weird to not go under it.
Level-Wrap is a bit off. Standing on a (standable) Thwomp which is wrapping at level boundary (doesn't matter if X or Y) leads to Mario falling off the Thwomp and often Thwomp hurting Mario. He seems to spawn into him.
Addionally walking on slopes through Level-Wrap seems to do not position Mario properly either.
Don't know if it's the same bug though.
Thwomp-Example (the SMB3 Thwomps are set to PlayerBlock on):
The lighting of all objects (if set) in a dark level is off. It should be always a circular lighting. But it's only shpaed properly like a circle if lighting value of an npc or Mario is set to 40 pixels or above. If set to 32 pixels or below there's only lighting shaped in a square which looks very weird. And it gets even weirder if you set the lighting value between 32 and 40. Then the circle and the square are visible.