Hi Rob,
from the log file (Version 2.5.1.14):
[19.05.2016 23:59:09] [DEBUG] [Sequence Thread] Canon Camera: Saving FITS file...
[19.05.2016 23:59:09] [DEBUG] [Sequence Thread] Created full file name (file does not exist): C:\Users\HCO\Pictures\Astro-SGP\M51\Light\600sec\2016-05-19 L_0001.fit
[19.05.2016 23:59:09] [DEBUG] [Sequence Thread] Extracting RAW data...
[19.05.2016 23:59:09] [DEBUG] [Sequence Thread] RAW arg data: -D -T -4 -W -v -t 0 "C:\Users\HCO\AppData\Local\SequenceGenerator\Temp\cannonRaw-0.tmp"
The "d" parameter would have been extremely bad for the calibration process.
Regards,
Horia