UPDATE: @SteamTrain seems to have solved my problem (by explaining what the heck TurboTax is adding up to create what only LOOKS like an incorrect total), but I will leave this earlier comment about my customer-service call up anyway. I'm not sure what the ongoing issue or glitch is, or whether there really even is one, other than the software's not doing a good job of explaining how it's reaching this "total."
I talked to the TurboTax help desk, which bumped my question up to the TurboTax "resolution desk," and the representative there said "there is an ongoing issue" with these forms not totaling correctly; "it's a glitch" and "they are working on it," but no date was given for when it is expected to be corrected. She told me to try working on my return again at the end of the week and see if it had been corrected by then.
