Pen table text substitutions work in print dialog, but not in print organizer?

I have a named expression in a .dgnlib to give me the sheet number and sheet total in a sub-folder of the print organizer (say for plan and profile sheets would be 1 of 10, 2 of 10 etc, but the overall sheet would be 43 of 250, 44 of 250 etc).

This named expression in conjunction with the pen table works when I use the standard print dialog (i.e. it fills in the placeholder with a 1 since there are no folder it is printing from when printing an individual sheet). However when I try to utilize it in the print organizer, using the same pltcfg file and the same pen table, I get "INVALID EXPRESSION".

Please help!