@KrisD15Thanks for the response.
I hadn't gone through the questions you mentioned about credits before because we don't have any. So I went back to make it ask me all those irrelevant questions so I could tell it "no." And now the references on Review to the phantom Child Tax Credit are gone. But that's a serious error that TurboTax, without any user direction, presumes that I have credits and forces the form (yet doesn't provide it to be deleted).
I can't fix the donation error. I tried the process you describe, but it doesn't match my interface; I think what you've described is from a different version of TurboTax.
I can correct the amount to the correct $600 directly on line 12b on the 1040/1040SR Wks in the Forms view, then save the file. On relaunching, the amount is still showing on that line in that form correctly. So far so good. But when I then run the Review again, on its own it replaces my correct $600 with the incorrect $300.
At this point I'll have to remember the workaround, and after my last use of the Review function, remember to manually correct the amount on line 12b and save it without running the Review again.
