Hi DadsAngry -
You're right in that Terror on the Thames was written for 6e and then converted - apologies if a couple of rules references slipped through in the process. If you spot any more corrections, feel free to message them to me and I will start compiling a list.
Most of the rest of the boxed set - including the other adventures was written for 7e - especially Those Poor Souls Who Dwell in the Light, which was written by Call of Cthulhu 7e co-writer, Paul Fricker. Straight from the horse's mouth, you could say.