Man, I'm giving away all my secrets here. :). Just kidding. I use the hard drive serial number adjust to six digits, which is what the codemine serial number requires for the first part. So if the user installs a new hard drive or installs it on an alternate drive, he will need to contact support for a new serial number

******************
** zGetHDDSerial
**
**	returns the last 6 digits of the HDD serial number.
LOCAL lcCurDrive, lcHDD, lcValue1
lcCurDrive=SUBSTR(SYS(5),1,1) && return current hard drive letter 'c'

**	return the hard drive serial number
ofs=create('scripting.filesystemobject')
lcHDD=ALLTRIM(STR(abs(ofs.drives(lcCurDrive).serialnumber)))
**	get the last 6 digits or pad with '0' if less than 6.
IF LEN(lcHDD)<6
	lcHDD=PADR(lcHDD,6,'0')
ELSE
	lcHDD=UPPER(SUBSTR(lcHDD,(LEN(lcHDD)-5),6))
ENDIF
return lcHDD

Following this I have a method that confirms the serial number, the first 6 digits must match the hardware id, then the serialhash must correspond to the second part of the serial number.