With a database updated from 1.3 (and probably earlier), when you go to AR -> Reports -> AR Aging, you get no results. This is because the stored function has this where clause:
WHERE not a.force_closed
Apparently a null value does not evaluate true here, while a false value does.
This column needs to be explicitly set to false after importing data from older schemas where it did not exist.
Same issue applies to AP.
Changing the reports from NOT force_closed to force_closed IS NOT TRUE. The latter handles null, while the former does not.