For accurate decoding it needs to be adjusted to the proper level.  My tapes have standard Dolby calibration tones on them so I can set the Dolby decoder, but I can  find NO information about how to do this.  Does anyone know how to do this or even if Magix considered this problem?

Every outboard Dolby B unit has a level adjustement for proper encoding and decoding and they also supply a calibration tape.  Without calibration the sound will not be correct.