If I had purchased a $5000 printer and could not make head nor tail of the operator's manual, I'd be right onto the manufacturer's Help Desk to get the info I needed.

I had a look at various combinations of *.ct? file extensions, and I could not find anything related to 3D printing either. Maybe it is an in-house extension for some other software that 3DSystems has?

That file extension does not come up on the 3DSystems website, either.

OME