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There's this bit in the forelimbs that tries to air-print, detaches, and has ruined several attempts (conveniently, the flaw is apparent quickly). It's the bottom of the pin that connects the claw inside the heel. The heel looks like a squared "U" on the first layer, then the second layer adds a little bit of a disconnected cross-piece at the top of the U. Printing in air, this doesn't attach very well, at least not in PLA on Prusa's PEI bed (cleaned with alcohol)! I checked both the original and new STL files, both Slic3r and Cura. I have tried all sorts of layer settings to get this to stay put, but even by setting the first layer to 0.4mm so it does appear in the first layer, it still breaks loose after a couple of layers ruins the print. Suggestions? (The attached PNG shows the problem area of the first layer on top and the second layer below for reference.)