Indeed your questions have been answered in this thread:
https://pixinsight.com/forum/index.php?topic=14129.0 . Again:
Skip the bias frames, they are not needed for a ASI1600. Capture light frames, dark frames (same gain, offset, exposure time as the light frames), flat frames, and flat-darks (same gain, offset, exposure time as the flat frames).
Integrate the dark frames to the MasterDark.
Integrate the flat-darks to the MasterFlat-Dark. Calibrate each flat frame with the MasterFlat-Dark. Integrate the calibrated flat frames to the MasterFlat.
Calibrate each light frame with MasterDark (no 'Calibrate', no 'Optimize') and MasterFlat (no 'Calibrate').
Debayer the calibrated light frames.
Register the debayered, calibrated light frames.
Integrate the registered, debayered, calibrated light frames.
Bernd