So what about the ability to disable unwanted API without deleting files?

Can you add it to the game launcher?

***

Oh, and by the way, there is also something wrong with videos in the GOG version. There is only sound and the screen is black. All codecs are installed and up-to-date and there is no such problem in the Steam version on the same PC.

You don't, but, as Sara mentioned, others, i.e. the double-dippers, do.

So to obey your request would be to screw them over. That's no good.

If you don't like how it is, then just delete the relevant file from your system to solve the problem. With that solution, no one gets screwed over.

Therefore, it's the best solution.

Indeed, the only reason this even affects the OP is because they're a double-dipper. They're an exceptional exception - they bought the game in both places but for some reason want to keep them completely separate. Despite there already being a solution for their exceptional case apparently it's not good enough.

No use arguing with a crazy person, they can't even get their story straight:
They did buy it on Steam as detailed in the first post, so by their own logic they must want it to interact with their Steam account. If they didn't want it to interact with their steam account they wouldn't have bought it there, right?

Hello Sara, thank you for all your support, which was very needed and helped illuminate the situation.
I responded to you as I think it is important to raise awareness. would appreciate your answer to the raised concerns.

Well, it's not entirely flawed logic, to say the least.
- There can be legitimate concerns to keep both versions separated, for instance when one is meant for Family Sharing via Steam while the Gog version only meant for personal Single Player, or maybe even meant to somehow play both versions in the same time (I assume when more than one screen is connected).
- There may be other reasons for double dipping - such as deciding to compensate a Publisher for a Gog release post already acquiring the game on Steam, perhaps not paying full price at the time.

- I for one, prefer to have most of my Library on Gog, but on the rare occasion when I have it on Steam previously (for instance if I got it on Gog via Connect), I almost never want to have the Gog version interact with Steam in any way, even if the Steam client was inadvertently running at the time of launching the Gog title.
Moreover, I would most definitely wouldn't want it register on Steam the time I spent with the Gog version, presumably completely offline (while Galaxy is not running) and it being published as Steam activity on my Steam Profile, not to mention unlock Steam Achievements - and I don't think it is strange to think that way, even if not the "common case".

Generally speaking, the way it is handled now is fine & the workaround of removing files is acceptable, but this should be advertised better,
As a feature listed on the main title page - "Unified version on all Storefronts & APIs" (preferably in both Steam and Gog),
Also at least a small print disclaimer (clickable for further details) on the game screen such as "Steam/Galaxy Integration Connected",
Preferably leading to a setting screen to allows controlling integrations as possible, including full enable/disable without tampering with files
- Too many games on Gog already cannot properly work without Steam files (or their stubs/placeholders) present, and it is illogical to expect the customer to keep a list of titles where these files are safe to remove,
Not to mention keeping the requirement of additional janitor work needed post any install, and presumably post updates
- Will updating the game on either platform bring back the missing API DLLs? I assume yes. What about Linux?

I didn't say it was unreasonable to want to keep them separate, I just said it was exceptional (double dipping is already the exception, so being a double dipper who wants to keep them separate is exception X exception). To expect Xseed to add extra options to the menu for an exceptional situation is unreasonable when it is easy to delete the file.

My reason for questioning the OP's sanity was due to the second quote. They say quite clearly that if they wanted the game to communicate with Steam then they would have bought it on Steam. Given that they did buy it on Steam, by their own logic they do want it to communicate with Steam and thus this should be a non-issue for them if we take them at their word.

Don't buy games on Scheme in the first place. Problem solved. It's because of letting Scheme ruin the PC gaming market that this type of verification would even be an issue in the first place.

While I'm not entirely familiar with the "general" double deeper mentality,
I would assume there are more Gog double deepers that would NOT like interaction with Steam, than the opposite,
- because the main appeal of Gog is being available offline and portable, otherwise why bother getting the Gog version?
Eitherway, even the double deepers who prefer such interaction would benefit from a small print notification that IT IS WORKING,
while those that don't want it, will have an easy way of listing it is there (possibly it wouldn't show if no integration was loaded).
Again. if XSeed will properly advertise this feature on the Game page (which they should as platform parity IS an issue),
Having the small print notification should suffice (but I and others like me will appreciate having a proper sub-menu).

I bought the game on Steam years ago when it first came out on PC and completed it.

When I was buying the game on GOG, I wanted a fresh, separate copy to complete it again and unlock some achievements. Instead, I received a "feature" that silently interacts with my Steam account and writes / imports data without my permission (Steam achievements were imported into GOG and I had to ask GOG support to remove them).

This "feature" wasn't mentioned ANYWHERE until this topic was created. The best way to make this "feature" clear to users is to add a couple of checkboxes to the game launcher. I believe it's not that hard.

And it really makes me laugh how some of you grovel in front of the developer / publisher here just because their rep showed up here and threw some magic dust in your eyes. What, expecting treats for being good boys? Pathetic.

Grown man acting like a child, grow up.

Not acting like a paranoid loon is grovelling now? We were (quite reasonably) worried that someone who didn't own the game on Steam might get in trouble for playing a "pirated" Steam game, that's all. Now we know that's not the case, the issue is resolved for the majority of us. If you see that as grovelling then knock yourself out.

Sorry for the necro, but I just realised that I could earn achievements for both GOG and Steam while playing Trails in the Sky FC. I think this is really cool and just wanted to thank you for making both APIs run at once.