[Hrabba Gunnarsdottir] “It does not seem to recognize the black magic converter. “
The converter is not an I/O device. It just converts a signal to another interface. If you need SDI you need to:
-Get an I/O device that has SDI out.
Or:
-Insert an HDMI cable to your GPU, run that through the converter and connect the SDI to your monitor. Then enable it in the playback settings. If I remember correctly it was called “fullscreen preview” or something. Note that the monitor is probably expecting some sort of a standard signal so your sequence needs to match that.