Update (11.11.2016):

I have updated my application, here is the new download link:
https://drive.google.com/file/d/0B2oQNJHDW6TUbkYwSnl1WnBBOU0/view

Here's the changelog:


-added the possibility to add up to 10 optional menu buttons, not just three

-the user can now choose images of any resolution, because they will be resized appropriately, just note that a much different aspect ratio will make your image stretched a lot

-changed the image format so that it matches the one currently used by Galaxy

-changed the default background image

-introduced a checkbox for applying gradient on the background image (so that the background image fades into the solid color, just like regular GOG games backgrounds) - it's not as good as I'd like it, but it's something ;)

-added the option to edit previously added non-GOG games

-fixed a bug which could cause images not to appear for an added game

-redesigned the application visually

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Hello all!

Some of us believe GOG Galaxy to lack functionality to add non-GOG games to its library. It's not that difficult to do it manually by creating some files in specific directories, but I think a simple application would do better.

Long story short, I decided to make such an application. It's simple enough, but it's quite versatile.

What do I mean by "versatile"? Well, if you wish, you can add custom background, logo and icon images, as well as add extra menu options (up to 3 of them), each launching a different exe (or any other file, really) in case your game has more of them.

However, at the minimum, all that is required is for you to show the app the directory in which the game is installed and type the name of its launcher, like "Game.exe". You don't have to prepare logos, icons and backgrounds, in this case the game gives your game the "generic galaxish" images - a GOG Galaxy icon as a game icon, a GOG Galaxy banner as a game logo and a purple galaxy background as a game bg.

I believe I've tested it thoroughly, but I'm sure some things might have escaped my attention.

Here's the link:
https://drive.google.com/file/d/0B2oQNJHDW6TUWTZfOF9lcWtxdHM/view?usp=sharing

I don't think this app can really mess anything, but just in case - I do not take any responsibility for anything at all. Use at your own risk, even though I don't think there's any. :P

And some additional pieces of information:
-this should work on Windows; you can try it with other systems, but I don't think it will function
-after adding a game to Galaxy with this app you simply need to import it like any other game to add it to your library
-as far as I've tried, you can remove a non-gog game from the library (not uninstalling) by choosing the "Uninstall" option in Galaxy
-the application creates random game IDs every time you use it. They are 15-digit long (as opposed to original GOG games with 12-digit long IDs)
-if you want to add the same game again for some reason (for example to add a Galaxy menu option) you should first delete the "goggame-#.info" file in the game's directory
-if you have any questions or find any bugs, post here; I'll do my best to help

Hope you like this. :)

So you don't have a Google Drive or Dropbox or any other service that doesn't look sketchy as heck then?

How is mega.nz sketchy? It has better encryption and more free storage space than either Google Drive or Dropbox.

But anyway, I've noticed the search button doesn't work for a background image (you can still write or paste its path manually, though) in the first version I uploaded, so here is an updated one.

And it's on GOOGLE DRIVE! :P

https://drive.google.com/file/d/0B2oQNJHDW6TUWTZfOF9lcWtxdHM/view?usp=sharing

And here's a scan if anyone would like to take a look.

https://www.virustotal.com/pl/file/5c1f4be47253d1d1d0912ca893cd4a41053778ea06c61d5d561499572ee54998/analysis/1452039356/

I tried to create as you said. but I still cannot add my non gog game like PES2016, Counter strike to gog galaxy... plz help me like in elementary school... I am relly new to it.
thanks.

Sure thing. The simplest way of adding a game is simply adding its exe and not including any custom backgrounds/icons/logos.

First thing to do is to fill the necessary (which is yellow) text fields in the GOG Game Adder. These are:
-Game title - here you type the name of the game as it should appear in your library in Galaxy
-Main EXE - here you type the name ONLY (not the whole path) of the game launching file. For example "cs.exe" (or whatever file you want to launch when choosing "PLAY" in Galaxy)
-Game folder - here you should type the path of the directory in which your main exe file (from previous point) is located. For example "C:\Program Files\Counter-Strike". You can also click the search button to select the directory instead of having to type it.

Once you've done this, press "Add game". Now check the directory of the game. There should be a file called "goggame-XXXXXXXXXXXXXXX.info", where Xs are some numbers. If you have this file, it means the application's job was successful. Otherwise maybe you should run it as an administrator, but I think it should work.

So if you have this file, all you have to do now is open Galaxy, click on the "+" button, select "Scan and import folders" and choose the same directory you chose in "Game folder" text field. Confirm and your game should be added to your library.

If you have any other troubles, ask here. :)

Thank you for the prompt reply.
Yes I have done the exact procedure and goggame-XXXXXXXXXXXXXXX.info was found in my game directory.
I added the games in Galaxy but I cannot find this .EXE fromGalaxy search and also I gave the same directory in which my game file is. Still it says No game file found.

I see. Could you send me your created INFO file to my mail? I'll send you the address via chat.
I'm asking because the only case I can think of that would disallow a game from being added to Galaxy is an invalid INFO file. I believe GOG Game Adder produces correct files all the time (I've tested this quite extensively), but there might be some special case I haven't taken into account. I think I'll be able to help you get your game to Galaxy if I see the info file.

Oh, and have you tried it with several games or just one? You might want to send me all of your info files if you have more than one. The more, the merrier! :)

Taro94 you're great! This makes things quite a bit more easy.
I've tested this application by adding Ether One Deluxe Edition to the GOG Galaxy client, I bought the game on Humble Bundle DRM free.
It works like a charm!

The great thing is I got all the art too.
What you can do when a game is also sold on GOG is grabbing the logo and the background from the site.
They will fit perfectly in the Galaxy client because they're literally the same files.

For those who don't know you to do this:
- Go to gog.com and open the games section.
- Search for your game until it appearn in the current page (don't use the search in the top right).
- Right click on the 'preview' image of your game and click something which says 'view image' (might differ from browser).
- Save the image to a folder you can easily find.
- Now go back to the overview where you found your game and click on it to go to the information page.
- This page has the background that Galaxy also uses. So right click the background and select something like 'view background image'.
- Save the background image to a folder you can easily find.

Now you can add both images with the Game Adder when adding your game to the Galaxy client. It looks perfectly in GOG Galaxy! :D

I'm glad you like it!

I stumbled upon a problem.
I can't seem to add the World Of Goo to the GOG Galaxy. Although the info file is in the correct directory it just says it didn't found a game.

Please send me this info file. Either upload it somewhere and post a link here or PM me and I'll give you my e-mail. It might also help if you specify what options you used to generate it. Meaning if you chose any images, if you added some drop-out menu options, etc.

I've added all 3 kinds of images, 2 jpg and one png (icon).
I've also added a drop-out menu option to launch a modding tool which is located outside the root of the game's folder so I used the direct path.
I tried to add the game by removing the extra menu thingy from the info file but that didn't change anything at all.
Here's a link to the info file: https://dl.dropboxusercontent.com/u/2980851/GOG_game_adder/goggame-939756781793626.info

Okay then, the reason behind your problem was something quite silly, actually. :) You used "\" instead of "/" and it looks like Galaxy doesn't like the former.

Use "/" and then try it with a direct path - if it doesn't work, then it means Galaxy dislikes direct paths, too, so you'll have to copy your "GooTool" folder into the root folder of your game and use a relative path "GooTool/bin/yourtool.exe".

That means it has to be the direct paths, which is weird because it also didn't work without the extra menu.
I'm quite sure it isn't the backslash because that's how I add all games.
But I'll try to change and see what happens. Thanks!

Edit: Looks like you were right. I think I might have deleted a bit too much when I removed the code of the GooTool option because it's now working with the tool added.
It was indeed the backslash.
One note though: it also indeed doesn't likes direct paths. So I'm reinstalling the tool now.
Thanks for your help and the wonderful tool!

That this feature isn't built into the client is a complete travesty.