This is my very subjective look at the versions of Subwar 2050. It's taken from multiple posts I made a while ago on the gog.com Subwar 2050 forum.
After a bit of digging around there seem to be 4 versions of Subwar 2050 and the version you are running may affect how successful you are throughout the campaign and the difficulties you may encounter during missions.
I'm a big fan of particle systems, the people who made this. Their later I-War/Independence War is still a personal favourite, but when it comes to their scripting system, not so much. It can be a bit flakey at times and sometimes downright weird. However this seems to have been something they both understood and worked on because in later versions of Subwar the scripting feels like it improved and missions which felt arbitrarily unfair seem to have been tweaked.
So in what I think might be a very rough chronological order, the Subwar versions:
Original 5 Disk version / CD re-release
This version doesn't have the autopilot or the swload.sav file which seems to store the custom weapon load-out. The sw.exe file seems to be from 1993. Although the CD re-release has the 'plot deepens' scenario included it isn't installed by default so you'll have to find it on the CD and install manually.
The original version, without scenario, benefits from having the v2.02 patch installed, which should still be available, to update sw.exe. this seems to improve the scripting but later versions seem to be, in my subjective opinion, even better.
CD re-release with plot deepens scenario installed
Running the scenario install, updates the sw.exe to the 1994 version. Autopilot is available and the custom weapon load-out swload.sav file is added, a definite qualify of life improvement.
I started playing the original version, not realising the 'plot deepens' scenario was included on the CD. I couldn't get past mission 4, after issuing special orders then setting my wingman to attack targets, trying to issue the special orders again would no longer work and sometimes the wingman would disappear off never to be seen again. Running the CD re-release with the scenario installed updated the sw.exe file to the 1994 version and fixed this issue.
Subwar 2050 complete
This is a multi language CD with french and german versions, it has the autopilot and custom weapon load-out, however the install only creates config and saves files on the hard disk whilst most of the game files remain on the cd, it uses a later version of sw.exe.
Subwar 2050 complete (gog version)
This is my subjective opinion but it feels like the GOG version is the definitive version and as such is the preferred version to use. The mission scripting feels less flakey than earlier versions and the weapon effectiveness may have tweaked to be slightly better.
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