In the section on addition, the second number added was always put first in the sentence. Of course, it did not make any difference, because of the commutative property of addition, but it is disorienting that the number subtracted from now comes first in the Klingon sentence. I would recommend translating the addition sentences with the same order the subtraction sentences are translated in.
This is the order Marc Okrand presented addition and subtraction. http://klingonska.org/canon/2000-09-holqed-09-3.txt
I am not questioning his knowledge of Klingon (I'm sure Molor is a very good teacher), but I would still suggest a different translation into English. Just because one creates a language does not mean one always chooses the most felicitous translation from it.