GrumpyElk: Here is an (unsatisfying) update from GOG support:
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snip
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I would therefor suggest not to buy the DLC (or the Amen edition) until the issue is resolved.
Pkmns: Thanks for letting us know. This is honestly absurd. Of course I don't expect GOG itself to fix this but they should force the devs to do something or take down the DLC.
I wholeheartedly agree. You first reported these difficulties nearly three years ago. And there still is no solution and not an ETA for it either. The DLC should not be sold anymore, if it cannot be accessed.
But then again, it is possible that not everybody is affected the same way. And for most people does the DLC in fact work? Even though I guess most people will not even realize that the DLC is missing as they wont finish the story of Ray Bibbia and wont be longing for more crazy bosses.
Anyway. I was advised by GOG to contact support directly via
support@headupgames.com
and
info@headupgames.com
I forwarded my ticket to support@headupgames.com and will keep you informed if I get any helpful reply.
Feel free of course to contact them too. Might help them realize that I am not just one single crazy person, but that the DLC is actually not functioning correctly.