Design view disappears when I uncheck Restrict Page Occurrence

Question

Dear Adobe Forms Experts,
I have an Adobe print form with two master pages: one mailing address page that should only occur once, as the first page, and then the main page, which can occur many times. I have been asked to make the mailing page conditional, based on the company code of the invoice. I followed a very useful discussion on SCN explaining how to do this with a HIDEPAGE global variable, wrapping all the fields on the page in a subform, and doing some FormCalc scripting for the subform.
I was able to get the page to print as blank when the HIDEPAGE flag was set, but so far I have been unable to get the mailing page to go away altogether.
I noticed that on the mailing page the "Restrict Page Occurrence" checkbox was checked, and the Min count was set to 1. Well, I thought, that could explain it; I'll just uncheck the "Restrict page Occurrence" checkbox, and all will be right with the world!
Wrong! When I uncheck that checkbox, the Design View for my mailing master page disappears, and the mailing page never prints, regardless of the state of my HIDEPAGE global variable! When I recheck the checkbox, the design view reappears, and the mailing page goes back to printing a blank page when my HIDEPAGE flag is set.
What in the world is going on here?! What am I doing wrong?
Cheers,
TerryB
P.S. I am using Adobe LiveCycle Designer 9.0, and I believe the form was originally created using 9.0

Answer 1

First off, in case anybody reading this in the future has any doubt, I will confirm that this discussion has morphed into the well-worn discussion on how to conditionally hide a page.
Pavan,
    I am now working on a copy of the original form, so I have the freedom to do whatever I want. First off, thank you for the suggestion of right-clicking on the "data" very-top-level node in the hierarchy view, and selecting "Insert subform". That did the trick for adding the missing design view for my mailing page.
    I am now trying to reduce things to their simplest form, to reduce the number of places I could be going wrong. The mailing master page now contains nothing but a content area (which appears to be required). The design view for my mailing page now contains only two objects: the "D_HIDE_PAGE" flag, (bound to the global field in the interface, where I have put the code to conditionally set the flag), and a subform called "Show_Hide", which is set to "flowed". The flag field is wrapped in the Show_Hide subform. I added the following FormCalc code to the Initialize, form:ready, and layout:ready events of the Show_Hide subform:
if ($.D_HIDE_PAGE == "X")
then
$.presence = "hidden" 
endif
    When I do a print preview on the form for an invoice that does not set the flag, I see the label for my flag field on the mailing page. When I do a print preview for an invoice that DOES set the flag, I get a completely blank mailing page--but the blank page is NOT being suppressed!
    Just for grins I also tried adding the same FormCalc code to the same 3 events of the top-level subform of the design view (the one I added by right-clicking on the "data" node in the hierarchy view; I called this subform "MAIL_DESIGN"). Same results as before.
    I believe I've followed all the steps laid out in the many SCN discussions on this topic--but obviously I am still missing something. Any clues where I may have gone wrong?
Cheers,
TerryB