Info about the bugged Uesugi unit:

It is fixed in my build (just replaced an entry with patch6 entry), unit just tested in Custom Battle mode without issue.
I still have to re-apply S2R+ stats for the unit, and i'm excited if or which value is causing the crash.

However, expect a new update-build at the weekend, incl. a working Uesugi Nagi Monk.