There is some info here:
http://www.xtemu.com/forum/game-discussion-f47/drm-gogcom-title-t3183.html&gopid=23620#entry23620
And here:
http://mudlord.hcs64.com/forum/showthread.php?tid=7&pid=9#pid9
Like... what the hell?

copyrighted crack ?

Hm, so?
Is Hoodlum crazy and going to sue GOG?
It's been done legally, with full acknowledgement from the copyright holders, so get over it people.
We've been through this with Arcanum already.;)

Don't care.
Then again, I don't really have a respect for "The Scene", as without them, we wouldn't HAVE Securom.
The crackers can go QQ more for all I care.

Oh, wow. The irony, stupidity; sheer retardation and pure ignorance.
This is... pretty fucking hilarious.

again...
crackers have NO rights whatsoever. their work? publisher, developers can TAKE and use as they please, without giving any credit.
I used bunch of cracks to make legal games work (stupid STALKER didn't want to run otherwise for some reason) and i am thankful for their help but they really should not be concerned about that stuff. heck. even proud maybe.
really immature bunch of people who seem to have narcissistic views.

http://www.gog.com/en/forum/general/gog_arcanum_release_uses_warez_scene_crack/perm=170/#p_b_170
Been there, done that. Move along.

Hahahahahah... Nice one! :D

As a wise man once said. CRAI SOM MOAR.
If the crackers want credit then they should go and start making games rather than cracking them

...sigh...

To be honest, I'm a little more worried that there are apparently some remnants of the DRM in the executable.

Yeah, he's raising MAJOR hell on his... forum(?), containing a total of... 6 threads (whoa) spread out over, yeah, 6 forum sections, and totaling a whopping... 11 posts altogether...
Clearly, this is a man whose word is backed by the majority of gamers :-D

This.

Why would it matter? It's not functional.

true. that is a valid concern. the thing is that drm might be embodied into the core of the program and simply cannot be ever removed without reprogramming a huge chunk of it.
it is far from simple: removing few lines of the program and there is no drm.
so as long as the drm is inactive the game is drm-free.
anyhow
cracks are illegal. so even if gog is thankful they CANNOT credit the creators.