"Gang Mask" in DRDDP LumaScript - How to set?

Exactly how does one set a 'gang mask' using the 'lumaScript-DRDDP DRD07 programming only.20200428.zip' script? Nothing I enter seems to make a difference, and many times, the script will change what I enter to '15', which isn't even a valid entry.
The valid values are supposed to be: 0, 12, 123, 1234, 234, 34 and 12,34
15 is not a valid value.
I would try resetting to factory defaults and try again.
Also, configure before you start lumascript
We're all confused as to exactly what to put in there to specifiy 1-ch, 2-ch, 4-ch operation. I don't know where '15' keeps coming from. My screen has been defaulted and reset dozens of times to run various tests.
It's based on how it's wired but....

1 channel is always 1234
2 channel could be 123, 234, or 12,34
3 channel could be 12, 23, or 34
4 channel is always 0