Send Checkdigit and Send Number System only affect the last or first sub-script digits in the barcode.
Expand UPC-A only affects UPC-E barcodes that use Number System = 0.
Addenda 2/5 Digit only controls the displaying of the addenda if scanned.
Addenda Required/Separator only works if combined with Addenda 2/5Digit, otherwise only the main part of the symbol is accepted.