Thanks for your help, but I am still having problems getting the correct full-value of the donation. The issue seems to be that the date of death was less than 1 year before the date of my donation. I experimented with different dates and if the date of death is more than a year prior, it seems to work correctly. But as I understand the rules, stocks obtained by inheritance are always treated as if they were held at least one year.
If my interpretation is correct, this is a serious bug in turbotax
