My point was that even though Microsoft is famous for changing for change sake that I can write a program on WIN-10 that can create an EXE file that runs on WIN-XP speaks to the respect for their customer base that they don't change the EXE format and version with every revision like Alibre does with the AD_PRT files.
The format of .exe files hasn't changed since windows was invented, but the difference is that Microsoft spend millions in either creating compatibility libraries, or you'll usually find the windows system directory is full of legacy .dlls that old .exe are linked to/built against, in order to make things backward compatible, something I'm 100% certain the Alibre team does not have!
As a software developer myself, that writes applications for Windows, the work to support legacy .exe applications is mostly done by Microsoft, but you still have to adapt and move on if you want it it run on newer OS's. i.e. where user data is stored, UI, memory management, etc.
But all that is just to make the application .exe run
. Application data
and it's structure/format is a separate thing ...
The file formats of data files (which is all the AD_PRT file is) is no different than Word or Excel files. It contains data that uses the latest features of the applications and in the case of Word and Excel you loose formatting styles, etc if you want to export as an older version. That's perfectly acceptable when the features are not critical to the data structure and are just an additive subset. This is the sole reason why file formats generally moved away from binary (specific data layout in the files) to xml formats. With xml, the application that loads in the data only needs to read the portions it can deal with and ignore the newer feature data sets.
In the case of Alibre, ALL features form part of a mathematical pipeline
(just like the Design Explorer depicts), If you take away a newer feature to export to an older version, that pipeline breaks
... it doesn't just mean missing a colour or something, it means missing an entire geometry manipulation step! i.e. If you export v26 as a v23 part, what happens to the fastener constraints data? What happens to the extrude different direction, different lengths data? If you just throw that feature data away, the part just won't evaluate.
No application is perfect, but sometimes you just need to move on. I was on Win7 until 2 years ago (absolutely loved Win7). Most of my good 'ole tools still run on Win10 though, using Windows Compatibility mode, not because I want to, but because for the sake of newer features and, in particular, security and stability support.
Just be lucky your not running productivity tools on an Apple ... won't go there, but lets just say that my outlay on Apple hardware and OS's just to keep ONE
legacy Apple application running (and updated) since 2006 is way more than I've ever spent on all my Windows products combined!