for example in this bit does the -1 mean it is removing the 1st digit and the 1 mean the value is 1 digit in length?
Depends on the function, I think substr which would be substring is the index for start and end. Or it might be start index and length.
Google the jscript function for definition.
BOOM!! worked it out first time!
used show message to see if i got it to display the correct numbers
Rule 1. New numberpad entered rule to strip digits to require pin
Rule 2. Changed existing numberpad eneterd rule to auto command exec rule and changef numberpadValue to CommandValue in the rule and action constraints and added the auto command name constraint
Just needed to create rule 1 and amend rule 2 and it works perfect now