I eventually deleted both Forms 2210 and 2210AI. I also carefully reviewed the underpayment penalty criteria and re-accomplished that section of the interview. The tax record now shows no 2210/2210AI, and no underpayment penalties. It appears this is the correct outcome.
For verification, you can also open the 2210 from the Forms view, and it will show the autopopulated data fields. It "appears" correct, in that 2210 Block 7 is less than 1000 (on mine it's negative); so the process stops (because there's no 'underpayment'). There are also no anomalous entries in Part II Reasons for Filing.
A "correct" 2210 may then exist in the software, but since it says to not file it, it doesn't show up in the current tax record (as seen when viewing "Forms in My Return"). At least I think that's what I've got now.
I suspect it may be a software bug with an arithmetic error somewhere in the 2210 process. Or it may also somehow be related to including non-taxable income in the Sales Tax portion. In a first draft, I didn't do that and got no errors. In the second, more detailed effort I did include the non-taxable income and did get the errors. This is anecdotal, and I'm not going to trial-and-error to see why the 2210/2210AI got messed up in the first place.
