Productivity modules cannot be used for any of the circuit boards in 2.0, despite that being one of the prime spots to use them. It isn't mentioned in the balance changes(which were very much needed). Is that intentional?

Productivity modules can be used in the intermediate steps, just not in the completed circuit board. Yes, it was intentional.

There were a ton of changes as part of 2.0 upgrade. So when going back through everything to write the changelog, it was easy to miss mentioning things sorry!