[RobotToaster]

Openscad can export to CSG, which can be imported by free cad or converted to STEP https://github.com/gega/csg2stp

[WillAdams]

Whether or no that will be useful/editable will be determined by what sort of objects and modeling approaches were used --- it's pretty easy to make a file which results in a nightmarish triangle mesh representation which is a nightmare to edit.