Okay, I've done some more experimenting. I tried exporting just the hooks as obj and re-importing them back into Carrara. They still show up all piled on top of each other, so I moved them back into place. Then I tried re-exporting the whole boot with the new hooks. Still get the hooks all piled up on each other. Then I tried exporting the whole boot as a dxf and a 3ds. The hooks show up in both formats in the right places. But the dxf version of the model is just way too blocky, and the 3ds isn't quite as smooth as the obj format. Anybody have any ideas why the hooks show up in the right places in these formats work, but not in the obj format?