1. Launch the GoG Launcher and select Neverwinter Nights 2.
2. Click the configuration icon at the top right which looks like this:

3. Hover over Manage installation, and click configure.

4. Uncheck Automatically update to newest version. Then select Version 1.23 - and click OK.

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It will get you the files you need (rather fast/almost instantly.) and you should be setup! Make sure you are running the client extender (NWLauncher.exe). Don't run the game through the GoG Launcher! If you need some more information on how to rollback - click here.
