One major translation error: in page 18 of the original ( https://e-hentai.org/s/a676298619/14280-18 ), Asahina says "Demo yokatta desu. Nagato-san ga inai toki ni konna koto ni natte...", referring to that it's good(/a relief) that it happened when Nagato-san wasn't there. That line is large, and followed by a background !?, because to us it looks as though Nagato-san /was/ there. It's then followed by the explanation that the others couldn't see her (related to evilness).
By translating it as "If there wasn't Nagato-san, I don't erally know what would have...", it implies that Nagato-san's presence was known and that it was good that she was present, but this directly conflicts with the !? and the following revelation that only Kyon could see her (and that Nagato's chop was interpreted as Kyon's).
Rather than a point by point interpretation, a complete overall understanding of a story is important when translating it. If you interpret something one way and then later come across something which overturns your interpretation, it is also important to be able to go back and rectify the earlier misinterpretation.