Hide or disable inputs on repeating promps

[cnoisemaker]

Hello,
I have a set of subreports with one common set of start and end dates used in all of the subreports in addition to some pick lists. I need a way to suppress them showing up - I am half way there-able to prepopulate them with the same values by using catalog prompt - but need to hide them from showing or atleast disable input on them.

  To explain my current application:(sorry for the long description)
  One main report ( which will finally bring results back to the user) with detailed and summary data based on a set of prompts - this is based on a datatable/view with metrics and keys.
  The filters in this main report go out to the appropriate subreports to get specific data and show up as choices at each step

Example: Main report: Products sold

Filter1 : 'Product key' in ?Active Product Keys? - need to enter a start and end dates for this.
Product Key is itself a child of 'Product Type Key". So, when you enter a set of Start and end dates in step 1 , it goes out and gets 'Active Product Type Keys'- based on the dates entered -  and then spits out a prompt box with the start and end dates and a picklist of 'Active Product Type Keys' - I have made the dates prepopulate with a catalog prompt- so no need to enter anything in the date prompts- as the start and end dates are common across all prompts.
To summarize, the above 2 are cascading prompts each based on a common set of dates and the second one additionally based on 'Active Product keys Picklist'.

Filter 2: Sale Type in ?Active Sale Types? based again on the same set of dates entered as in prompt 1 - no cascading to anything. Returns a picklist of 'Active sale types'

Filter3: Sale Date between start and end dates - again the start date and end dates are the same.

With the 3 filters, I get the prompt box showing up dates 4 times (although prefilled in the 3 times each goes through other pick lists and  final prompt box).

I understand there is a way using the openreport method in a macro.
Where do I embed my Openreport macro in?

Is the export to csv and read back values from the only method? If so, if I save the save the csv on the same folder as the reports, any issues if more than one user tries to run the report- how to name the csv for each users inputs?

Primarily, I want to stop the Start and End dates prompts showing up after step 1 - feed in the background to the corresponding reports. If this is not possible, can I make them like display fields - no input allowed / changes allowed?
Any help in detail is appreciated.
Thanks