I just did a quick test, and it confirmed what I suspected. a step file of a speedpak configuration does not save any 3D solid data. (didn't even save any surfaces.
also, speedpak doesn't simplify any sufaces (i.e. no hole filling, no fillet removal, etc.)
I am under the impression that SpeedPak saves only surfaces.
I am not surprised that they do not translate to an export format.