...Additionally I had to right-click on those fields in 2210 Part1 Line 10 and choose "Override" so that I could enter data. After that, TurboTax did not recalculate all the rest for me. I had to manually compute values and individually override all dependent fields. In my case, the penalty/underpayment went to zero, but the previously computed interest lingered until I cleared it manually in the Part 2 "INTEREST" worksheet.
