I suspect that file is used to populate that list, too, and if so, you should be able to edit the order in the text file.
Thanks for the link...
I too, was unaware that one could access this file, however, in CS6, the file does not exist. I've posted on that forum to see if anyone has an update as to where to access this file or information on a newer version... crossing fingers.
It appears you are correct, which means it can't be used to fill that list (in looking over my own system, I have dozens of custom sizes for new doc, but no custom sizes in that list, so I was probably wrong anyway).
That sort of data -- certainly the custom new doc sizes -- is stored in InDesign Defaults and disappears when you reset the prefs. It's going to be a pain, but you might try renaming the InDesign Defaults file and see if the list is gone the next time you restart, then enter them again in the right order. See Replace Your Preferences for my recomendations on on what else you'll want to back up first, though.
Actually the link shared by Peter was the option till Cs4 as there was no option to create the Custom Page Size, however from CS5 onward the option was included within Document Setup window.
The Custom page size are included in the preferences at the below location, so Preference would be a bad idea:-
C:\Users\manish\AppData\Roaming\Adobe\InDesign\Version 8.0\en_US\Page Sizes
as the XML file.
If you want to change the listing , open the XML in Wordpad and move the "SA Web" and "NSC Web" over the "Well_web"
The way this drop down list the page size is the sequence they are written in XML file.
NOTE:- Do make the back up of preferences before making any changes.
Missed on informing that you have to move the complete coding.
<Name>"custom page size name"</Name>
I've just gone exploring, and I have dozens of custom page sizes loaded in Document setup, but none inthe pages panel, and no Page Sizes.xml files. I have a Page Sizes folder for CS5.5, but it's empty, but no such folder in CS6. Samre custom pages are loaded in all versions.
This Page size folder doesn't exist natively it get created when we define the Custom page size.
I just checked and I have it for CS5, CS5.5 and CS6, having an XML file in them.
I would say Back up your preferences, open Indesign CS5.5 , Create Custom Page size and then check. Do you get that folder created with the XML file.
I'm not worried about it enough to go through the hassle of replacing the prefs. Seems odd to me though that I have the folder already in both CS5 and CS5.5, and that both are empty. I have exactly the same list of custom page sizes in Document Setup in all versions since CS2, I think, and I got them by using the Load button in the define dialog. None of these custom page sizes appears inthe Pages Panel dropdowns, so I'm finding it very hard to believe that the xml file you referenced has anything to do with the Document Setup dialog.