I can't find any way to enter the correct taxable amount other than putting it in on 2a in entering my 1099R form (which makes it different than the company actually sent to the IRS) and leaving the 2B boxes still checked. Then TurboTax seems to calculate a reasonable answer.
If I leave 2a blank, matching the company's IRS submission, and answer no to the question re: if it is the taxable amount and let it ask more questions, I go down a rabbit hole of crazy questions making no sense on the form that pops up, and TT then tells me the taxable amount it's using is zero (wrong) yet the totals still reflect still taxing the whole thing (really really wrong) rather than the correct tiny amount it should have used.
Calling it a bug. I'll just fix 2a manually and cross my fingers since it does seem to calculate correctly in that case.
