Answer on BMD DVI extension:
Have a look in the product manual, you will find that if the resolution is NOT a valid SDI signal (480 – 720 – 1080), at the other end of the coax you will absolutely need the BMD Deck Link to provide back the resolution witch is NOT a valid video signal.
Otherwise, set your PC resolution to a valid scan lines, and your are in SDI, SD or HD.
It is in the SPEC.
AL