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I found the SK Mannequin file here:
https://www.dropbox.com/sh/0izkce9llhf9 ... in2.0?dl=0I will give it a go to get it loadable inside iPi Studio correctly, but it does come in very large and rotated wrong, as UE4 uses a Z-up axis.
I will let you know if I find an optimal way to do it, but I don't have UE4 installed for client tests.
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I was able to open the Mannequin file in 3ds Max and re-export it using scale as millimeters with a Y-up axis and load it in as a target character in iPi Studio and characterized it, this is what was achieved:
https://youtu.be/E_gN5s_NYHgIn theory, since I don't have UE4 installed, if I reversed this process upon export out of iPi Studio as an FBX, I should be able to import it into UE4 and things work fine also.
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Well, in testing after FBX export, it seems the iPi characterization won't allow the "root" to be used, so the animation is exported fine, but isn't on a stable axis, so you would have to re-parent the hips to the root of the original file in Motion Builder or use a dummy node in 3ds Max and parent it to the hips to stabilize everything again, or retarget it back to your original Mannequin rig and plot it for export.
I am not sure how UE4 allows animation files to be imported, just as animation without the skeletal mesh, maybe that would work too.
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I found this from Joe that might help explain things with the retargeting just by using the Motion Builder preset skeleton for export from iPi and importing into UE4.
https://www.youtube.com/watch?v=C6nmvcMSjzEI saw he didn't use a skeleton file on import into UE4 as you did, maybe that is your issue, as it creates one for you if "none" is left for that dialog and I didn't think you had to go through all you did to get an animation from iPi to work seamlessly inside UE4.
I hope any of this will help :)
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