A person on Steam called Killah has enabled it on the Steam versions of the game. I've tested it and it seems to work on GOG's versions as well.

(These patches will want to replace files in your GOG game directory. Allow them to.)

I've posted a direct link to the download links from the Steam link if you don't want to click the Steam links.

For Dungeon Siege 1: (Dungeon Siege I (Legends of Aranna) Steam Fix by Killa)

https://steamcommunity.com/sharedfiles/filedetails/?id=1148174213

Or

https://pastebin.com/Gcg9qLLp

Install instructions:

1. Click on the download link from the above link
2. Copy the 'Main MEGA Link' URL and paste it into your address bar.
3. On the download link look on the right corner of the screen and select download everything as a zip file.
4. After downloading open the Killah's Steam Fix.
5. Copy everything inside the "Dungeon Siege I Steam Fix by Killah" folder inside the archive to your Dungeon Siege GOG installation folder. Replace anything it wants to.
6. (Optional) Copy the reg-patch to your installation folder.
7. (Optional) (If you did step 6.) Install the registry fix as Administrator by right-clicking on the fix and then click Run as Administrator.

For Dungeon Siege 2: (Dungeon Siege II (Broken World) Steam Fix by Killah)

https://steamcommunity.com/sharedfiles/filedetails/?id=1165078098

Or

https://pastebin.com/Gcg9qLLp

Install instructions:

1. Click on the download link from the above link
2. Copy the 'Main MEGA Link' URL and paste it into your address bar.
3. On the download link look on the right corner of the screen and select download everything as a zip file.
4. After downloading open the Killah's Steam Fix.
5. Copy everything inside the "Dungeon Siege II Steam Fix by Killah" folder inside the archive to your Dungeon Siege II GOG installation folder. Replace anything it wants to.
6. Copy the reg-patch to your installation folder.
7. Install the registry fix as Administrator by right-clicking on the fix and then click Run as Administrator.

There are also guides on those pages for setting up multiplayer. Though i've not tested that.

A note:

You will get a message popup on both games after creating a character asking to select a world. Read the descriptions in game as they will say what is the original game, and the expansion.

Also it does not break Dungeon Siege 2 on Windows 10, mouse works fine (Steam version, and Retail had issues.)

Edit 22/11/23: Yes the registry files are needed for Dungeon Siege 2 otherwise the expansion will not see the base game installed, then the expansion will not see the base game installed so you need them both! (Dungeon Siege 1 remains optional as both the base game and expansion read each other differently.)

Language pack installation:

(Dungeon Siege I/II Language Packs)

https://steamcommunity.com/sharedfiles/filedetails/?id=1165078098

Or

https://pastebin.com/Gcg9qLLp

Install instructions:

1. Click on the download link from the above link
2. Copy the 'Main MEGA Link' URL and paste it into your address bar.
3. Click on the button with the little dots to your left on the file you want to download.
4. After downloading unzip the file you just downloaded.
5. Copy everything inside the the new folder we just unzipped to your Dungeon Siege directory. It will want to replace game files, let it.

A note:

Both games will work the same way to install the language pack.

DS1 seems to only change the main menu and general game hud to whatever language you have installed. Voice overs and text dialog will remain in English.

DS2 seems to change voice overs and text dialog to whatever language you have installed. Main menu and general game hud will remain in English.

Thank you for this!

Thanks a lot, dude!

Something like that. Though if GOG follow suit like they did with my Diablo guide I give it a month or so till they get here.

DS and DSII were published by Microsoft games and the rights were sold to Square Enix to make DS3.

DS:LOA was published by Microsoft and Mad Doc Software (who are now 2K Games) and DSII was published by Microsoft and 2K Games.

So since 2K now owns the publishing rights to both those expansions my guess is they're the ones holding up the release of them on Steam / GOG. Or that nobody has really contacted them to inquire if they will publish their games on Steam / GOG.

Are the steps 6 and 7 optional in Legends of Aranna and Broken World or just in LoA?

I always get a bit nervous about alowing unknow alterations to my registry.

you can always edit the .reg file and see what gets added.

Thanks a lot RoboPond!

I still have the original CD with expansion but I had technical problems to run it on newer Windows (flickering and mouse lag). Now it works nicely with GOG version and your procedure :-)

No. Broken World needs certain registry entries to run. Basically it looks to see where DSII is installed to.

You can always right click on the registry file and click 'Edit' to see what it does.

DS1/LoA does not need to do this, that's why they are optional, and Broken World is not.

Do you know if the language packs in the links includes french dubbing for both base games and expansions ?
I ask the question for me and for users on the french sub-forum who are dissapointed to not have french voices, even for the base games.

I've just tested this.

DS1 will have English voice overs and text when talking to characters, however the main menu and general game hud will be in French.

DS2 the main menu and general hud will be in English, but voice overs and text when talking to characters will be in French.

I assume for the other language packs it will work the same, though i've not tried them.

I've also added language pack installation to the main post.

Thanks for your tests !

Just a reminder that there was also 2 official mini expansions that where created from Gas Powered Games and Mac Doc Software

*Edit* I just read the guide from steam and it includes these expansions already apparently. But I'll leave the link here for them just in case.

Yesterheaven
http://ds.gemsite.org//web/index.php/maps/GET/detail-1

Return to Arhok (Legends of Aranna required)
http://ds.gemsite.org//web/index.php/maps/GET/detail-6

Ok Thanks for the reply! :)

Side Note:

I'm getting problems on the first link (Corrupted file and others errors), but the second link for each download worked without a problem!