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Please follow one of these workarounds:

a) Redownload the game using the newest version of the GOG Downloader:
To download, make sure the " Downloader mode" is switched to ON before clicking the "Game installer" button. After the download is complete, reinstall the game.
b) Use this workaround if using the Download didn't help:
- Go to Applications -> Terminal
- Type in:
xattr -d
but don't press Enter.
- Drag the application to the Terminal window, this should add the path.
- Press Enter.