Brother, I've been struggling with the exact same thing. Following you in case you come up with an answer. My smaller sprite/objects get stuck too if they turn near a wall
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yeah, its a head scratcher. I can't seem to figure out exactly WHAT gms2 uses as the border... I've tried multiple different sizes, I even tried making a 64x64 sprite with just a small image in the bottom of it and tried multiple different collision mask sizes, origin point positions... and the only on that has an effect is moving the origin point because that is where the path is drawn from. I'll let you know if i have a breakthrough!