I maintain a list of version discrepancies between offline installers and GOG Galaxy builds, it's available here:

https://airtable.com/shrldLsErlUf3eHqS

I've created this thread at (ø,ø)'s suggestion, so that people unaware of my API forensics thread can easily stumble upon it with a forum search and know that such a thing exists.

Now, for a bit of FAQ:

1. How are you generating this list?

I'm collecting a bunch of GOG API data on a daily basis, including offline installer versions and Galaxy build versions. I have a script that goes through the collected data and generates a list of mismatches, which I then validate and update on Airtable. None of it, with the exception of some manual overrides, deviates from what GOG's API reports.

If anyone is interested in how I do that precisely, the code is open source and available here.

2. You've listed a discrepancy that is actually solved by an offline patch included with the outdated installer!

These sort of situations are rather hard to track unfortunately, so (for the time being) I only check the main installer version for the comparison. Do let me know of such cases and I'll filter them manually.

3. Some entries have newer versions in their offline installers and older ones in Galaxy! What gives?

Usually GOG forgets to mark some Galaxy builds as public, which is sort of an issue. These "reverse" discrepancies aren't useful for keeping track of outdated offline installer, but are also a kind of problem captured on this list.

In essence this sort of situation is caused by API visibility issues, since a newer version of the offline installer can't exist without a corresponding Galaxy build. It's just that the Galaxy API doesn't list that version of the build for one reason or another.

4. The versions are different, but their content is the same! I've checked!

Drop me a message here and I'll include a manual override in such cases. There's no way to automate these sort of things. The script generating this list only employs a glorified string comparison (with 100 exceptions and corner-cases, since we're on GOG after all).

5. Your list is outdated!

I plan to refresh it roughly once every two weeks (up to a month, when life gets otherwise hectic) so do expect stale data to creep especially into the more recent entries. The general goal here is to track long-time offenders, not to provide an always in-sync list of discrepancies.

Offline installers lagging a week or two behind their Galaxy builds are not all that surprising on GOG, but some lagging months (or even years) behind are indeed a problem.

Thank you for providing this service.

Thank you for doing this. Now everyone can easily check if the games they plan on buying are kept up to date on GOG :)
Added topic as favourite for easy access.

Stargate: Timekeepers?
That hasn't been released yet.

Did some tests:

Tesla Effect, Darksiders III and Galactic Civilizations II, despite different numbers, are the same game version. All three of them seem to be classic GOG version numbering shenanigans instead of actual game version.

Journey to the Savage Planet, while the offline installer is outdated, you can download a patch to the latest version.

Offline installer for Serpent in the Stagland is outdated (v18) while Galaxy install is up to date (v19). Latest version was released last month (december 2023).

I tried Heroes of the Lance, Shadow Sorcerer and The Bard's Tale: Remastered and Resnarkled, but I don't know what to look for to see differences.

Galaxy install of Deus Ex GOTY: Revision is outdated (v1.6.1) compared to offline installer (v1.6.3), but considering that the entire mod available here on GOG is outdated (latest version is v1.7.3.1), I don't know if the mismatch is good or bad. Base game Deus Ex GOTY is fine.

Disciples II: Rise of the Elves is fun. The offline installer is an incomplete v3.01, as reported multiple times in the subforum, since it lacks the additional mini campaign from the Gold Edition and game number is v3.0, while the Galaxy installation is the full v3.01 GOLD (internal version number is correct and it includes the mini campaign).

If it has a build and an offline installer, I'm assuming it's either in a closed beta or perhaps a very closed alpha. The API doesn't lie, but it doesn't exactly explain itself either :). Thank you! I'll include your findings when I next refresh the list. Will add manual exceptions for cases where the content is the same or the discrepancy is fixed by a patch - note that these exceptions get reset by the script whenever either the offline installer or galaxy build version reported by the API change, so if there's any movement in the future they'll show up again in case it's not the right kind of movement.

Also forgot to mention I don't really use Galaxy, so can't test any of these myself. I have to take what the API reports at face value, and that is what the list is mostly. That being said there are some manual exceptions I'm already applying for ancient installers which are long know to have the same content despite versioning differences.

It is the release version, and the explanation is that during the final testing stage, almost a day before the initially scheduled release last month, serious issues were discovered, prompting their decision to delay. The new release date is now confirmed for January 23rd.

@WinterSnowfall thanks for the work you've put into this project!

To expand a bit some of the things I missed, it seems Heroes of the Lance and Shadow Sorcerer are just Galaxy specific fixes.

For The Bard's Tale: Remastered and Resnarkled, I saw in the subforum someone reporting a crash with 2.2.a but got fixed with 2.2.b. The crash doesn't happen to me so I can't say if it's a fix or not. The specific crash mentioned that seems to be fixed is a different one related to Windows 7 that is also mentioned in the subforum.

For Serpent in the Staglands, there is no patch available to upgrade from v18 to v19, and the internal game updater for v18 seems to not work.

Btw, I might concur on the first two, but the Galactic Civilizations II discrepancy was detected rather late in the "GOG geological age", certainly long after classic GOG version numbering became extinct. I think Stardock may have actually modified the game without bumping its internal version. Now I'm not sure if that was done just to add a teaser to GalCiv3, but I'm pretty sure they did something. *Sigh*... they should still bump the offline installer versions in this case :/.

It'd help with consistency, yes, but it'd make it appear that updates exist even though they really don't, and plenty may be wasting time/bandwidth applying them. And if they won't be flagged as updates, there will be questions about the blue dots being broken again.
I'd say it'd be better to state somewhere, very visibly, not just in the changelog, that version X is just for Galaxy and identical to version Y when used without Galaxy. Won't help your script, but will make filtering out these cases trivial.

PS: Nice to see this list finally get its own thread.

For Galactic Civilizations II, most of the differences are in Galaxy related files. There is one .dll located in the same folder as the Ultimate Edition executable that is different though and it seems it is from GOG, but I have no idea what its function is. Ingame, there doesn't seem to be any difference, no ads for GalCiv3 or GalCiv4, but I have no entered the multiplayer/online menus of the game since I don't have a StarDock account.

In the case of Heroes of the Lance, all differences are in Galaxy related files. The Galaxy one has a link to support while offline one doesn't have it. But that's it.

For Shadow Sorcerer, while most of the differences are in Galaxy related files, one of the DOSBox conf files is different. For some reason, Galaxy install defaults to window mode, 1920x1440 resolution, scaler normal 3x, mouse sensitivity 50, while offline installer is set to fullscreen, original resolution, scaler normal 2x, mouse 100. No other differences though.

They just updated the Star Wars: Jedi Knight: Jedi Academy offline installer only to add a TM after each term :|... it's not that you're wrong, but no-op updates are already being done. If they're being dumb about a thing I'd rather they're consistently dumb, rather than doing it sparingly, whenever the GOGBear wakes up in the morning and thinks it's necessary.

Or Galaxy-related updates could have their own revision numbering system, independent from the one used in offline installers and ideally the game itself. But I doubt things will change, so we'll have to live with the status quo.

Thank you for the in-depth analysis. In these cases when we're not entirely sure what has changed, or even if it is a simple config file, I would still mark it as an inconsistency, since the content is not in sync (which is how it should be ideally).

Heroes of the Lance sounds harmless enough, I'll manually exclude it for now.

Outlaws: Galaxy version has a file missing (so no musics), offline version works fine

Please take this up with GOG Support to hopefully get it corrected, otherwise it risks propagation to the offline installer at some point.