I think this is the same issue we resolved here:-
As stated, I really think GOG packagers should include this in the postinstall.sh, 64bit Linux doesn't provide fully featured 32-bit environment the way Windows does with WoW6432, and nobody in their right mind, wanting to play video games on their PC is running a 32-bit OS these days.
When you say Ubuntu 14.04, you're probably not talking about the ARM, DEC, or ia64 builds, but in gaming, you're also more likely to be using x86_64 than i386. (unless you're using GOG because you have a shitty rig and can't play contemporary stuff...)
Short version,the line that got all the libraries I needed going was:-
sudo apt-get install libsdl2-2.0-0:i386 libsdl2-image-2.0-0:i386 libcurl3-gnutls:i386
@miwioa sounds like you're missing the multiarch to me? If so, to correct the typo in earlier posts on this thread:-
sudo dpkg --add-architecture i386 && sudo apt-get update
Which should be run before
Agreed it seems odd that these are not included in the sh script at install as majority of linux users are now 64bit.