I was told that long ago there was a separate 'Pro/Program' module that used Visual Basic and could execute arbitrary code, such as for controlling the generation of file exports and running of different modules of Pro/E.
I know that PTC has borrowed/recycled module names to do things that are completely different from the original, but I don't have a clear recollection this was the case for Pro/Program.
You might consider looking through the download archives. You never know what you find.
I still have a lot of "Pro-Jr" stuff. If it was there, it would be mentioned in one of two gray real paper manuals. Still have the CD's too.
1st, I looked and saw no VB reference in my desk references from Pro/Jr days.
I think we had perpetual rights to previous releases. This could change some day as SW is forcing "subscriptions" onto people to go into most of their account including downloads (which NEVER worked for me, and SW support failed 4 times to correct)... what was I sayin' oh yea, I order all new releases on DVD and I downloaded almost everything I may ever need. It is a huge collection that took weeks to download onto a dedicated drive. My V19 disks saved my bacon a few years back.
...It looks like physical media is the limitation. Of course, the older version sites are hit and miss.
I give PTC kudos for including shipment of physical media without a fuss. You practically have to beg them out of SW's hands. And 2015 sp5 doesn't exist on media, believe it or not. It wasn't worth their time. This is why PTC got my maintenance dollar and SW didn't.
Not sure about Pro/Program and it's history. I guess it didn't change at all throught the WF and Creo days, so it propably always was internal to Pro/E.
For file exports using VB have a look at the Interface section in the VB API user guide located in <creo_install_dir>\Common Files\<datecode>\vbapi
Interest piqued, I looked through the code. As best I can tell, "Pro/PROGRAM" was consistently used to refer to the functionality once found under 'Program' in the top-level assembly mode menu, and now Tools>(Model Intent)>Program. I'm not sure how it was packaged long ago.