OK... I finished reflashing my N800 clean, it finished doing the SSU update and it didn't have any problem.. and now the backup tool is restoring everything. So far, so good! It appears to have worked fine the second time I did the SSU (mind you, there's almost nothing on it at the time). The way things are going, I expect it to be completely back to the way it was within the next half hour or so, once I finish tweaking things back to the way I like it.