do you still have the mechanism parts of the corners in the puzzle?
doing so will make it turn a bit easier and be less likely to lock up.
I truncated each corner to a triangle (with vertices touching the corners of each center), and filled in with Apoxie Sculpt where I cut off too much, so that the corners could fill in the space between the edges better than just leaving the track parts of the corners in. I did my research
Thanks for the responses, everyone. I'm going to try a 2x2 rhombic dodecahedron with an Eastsheen keychain cube next, probably going to fail, but it should be fun if it works