How do I convert a facet Body to a solid so I can move it to Sync?
For the future, you'll be able to convert scan data in .stl format in ST10 with reverse engineering:
in the meantime (ST9) try to import this STl file into a part.
This imported body - at the moment - is not be usable for "anything".
But, export this geometry to ICF and import that one again.
This - at least it worked for me - does a good job, even with ST9
With ST10 - as mentioned - this issue wwill become easier.