Like I said before, since WRMK 'insists" WE, the crafters, are incorrect and they aren't going to correct the guide, I printed Bugga's c/s measurement and score measurement with my labeler and stuck it above the ruler thingie so it's handy. By the way, the tape in my labeler is white and prints out black letters/numbers so is very visible.
The envelope maker is not defective, the manufacturer is giving out incorrect information.
The product is easy to use and it is fun to make envelopes to match your cards. Makes it extra special for the recipient of your card. They will be so impressed that you took the extra time to make an envelope especially for their card!