Bugfixes

• Last two versions did not ship with files required for manual backup.  Manual backups were failing, now fixed.
• View unit would display formula error in some circumstances. Specifically : view a unit on the floor where a formula cost like Stamp Duty was already added to sale cost.  Click view rebate and then close and go back to view unit window would trigger the bug.  Now fixed.  Cause:  formula functions are actually recursive under some circumstances and need to track whether or not they have already been called to avoid prematurely releasing resources required for formula calculation.