>The problem we are encountering is that the Adobe activex ocx will only save the changes to disk if the workstation has the full version of Adobe Acrobat installed. If only Adobe Reader is installed then the pdf form is saved without
I'm not sure this will be of much help, but I've been down this road as well and didn't find any particularly great solutions. From what I saw, the Javascript that you can embed in the document has a bunch of security issues (and missing objects) that pretty much keep you from being able to write anything to disk (or anywhere else that might be useful).
I did eventually find some info. about a way of pushing form variables into some configuration file that Acrobat has. The major downside to this was the limited amount of space available for this (less than 1k, if I remember). I'm sorry, but I don't have the link. I found for most forms that this wasn't nearly enough.