After reviewing this one with the ProSeries team, it appears that you are required to fill out Part I of the 6252 for all years of the installment sale. This is a change from last year. Hope this helps clear things up, as we should have our help articles updated to reflect this soon.
Yes that is what it makes you do now. You have to look back to say 2007 when the installment sale started and pull over all that data at the top before it will calculate correctly. The program pulls forward the % that is subject to tax but then won't work unless you re-key in all the old stuff from prior years. It doesn't pull over all that prior data that it now says it needs.