Sounds good and there's no rush. Whenever you upload it, just place a disclaimer and you're good to go. Hopefully you'll get some detailed feedback as well. Either way, appreciate the effort. :)
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No probs!

I regularly make my own "upgrade" patches for lots of older GOG games where I've patched updates to DOSbox or ScummVM, added missing files and extras, upgraded music, etc. and figured I could do something like that for this game but as a *downgrade*, given the unique situation. I'd love to help others with it too.

I would like to keep the file size down but technically a full downgrade does include patching all the HD videos and music tracks back to their 1.0.5d file versions, which adds around 700mb.

The other thing that proved a stumbling block is that saves are rendered incompatible by the update, so when I downgraded the saves no longer worked... this can be worked around with external tools and I am trying to incorporate that into my patcher, but worst case people will need to first back up and then convert their saves manually if they want to keep them.

To actually get back the previous version, I think most people wouldn't mind starting over. It's a small price to pay. Plus they get the patch files to revert to older version forever (once it's completed of course), which is unlikely to happen with the Aspyr update incoming for the current version. Unless GOG can (or is willing) to ask them to add the older version temporarily until the new update/hotfix arrives.

It might still help those who may have kept older saves for future use for whatever reason. I don't know about TR I-II R, but having a save (or at least the profile files) can help get back the unlocked achievements for games that were later reinstalled for replays and whatnot.

I think Soulstone Survivors is one such game that once you unlock new classes or features, they stay unlocked for future use of the proper files are backed up for use later on.
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Edit:
Oh yeah, I just recently played Tainted Grail: Conquest, which can unlock all village features once get find everyone and unlock additional classes once you get enough score points (win or lose). So I am keeping a copy backed up of the player files in case I have to reinstall it at some point in the future. Saves me the trouble of unlocking them all over again.

Now that I think about it, I wonder if someone should start a thread for games where backing up save files (or profiles) may come in handle for future replays lol. Some are fun to start over fresh, while others are a pain to unlock all just to play your favorite classes. =P
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I finished my unofficial patch, see here:
https://www.gog.com/forum/tomb_raider_series/unofficial_tomb_raider_iiii_remastered_downgrade_patch_for_gog_version

Great job! Thank you for all your efforts. Not sure when I'll install the game, currently playing Stellar Tactics and that's a really long game lol.

But hopefully someone who owns the GOG version can test it out and see how well it works, as well as provide any feedback. Here's crossing some fingers to see if anyone will post some updates. :)
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