Actually I was just trying this code and keep getting "Operator/operand type mistmatch":

proIn = 61227660  &&RLCA

lnDigit = m.proIn - (INT(m.proIn / 9) * 9)
		chkdig = 9 - lnDigit
		
??proIn + chkdig+CHR(13)+CHR(10)

It must have something to do with the proIn field because the chkdig is generated fine by itself.