Thanks, the game did not start on my Mint installation too, but your workaround fixed it.

I'm on MX-18 and I had this library missing too. But installed it separatly. BUT, it does not stop there. I also got this:
/usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `CXXABI_1.3.11' not found (required by ./TransportFever2)

I can for the life of me not see what is missing. I seem to have all of the latest of these 'libstdc++' libraries (supported by the distro) installed. So I have no idea how to add this in order to get the game working. I do not want do mess too much with the compiler libs since it can mess up the distro. Did no one test this release?

I know nothing about MX Linux I'm afraid, but a quick search for your missing lib in Ubuntu packages site gives this result, you may want to look for one of those packages in your repos.

But I would advise to not compile an old and obsolete library by yourself if that only possible because it's troublesome and in worst case scenario can even lead to system wide problems, I'd suggest to try my original workaround first and see if it works for you.

Thank you for your reply.

MX is essentially debian. So far I would say that it is the best distro I have tried in years. Very quick and extremly stable and it works quite nicly with basically anything I throw at it. All except Transport Fever 2.
Now my issue is that the distro run version 6.3 (64-bit) of libstdc++.so.6. This version do not contain CXXABI_1.3.11 but stops at 1.3.10. My problem consists in that I do not know how to get this 1.3.11 version.
I have reached out both to the devs and the MX forum. We'll see who answers and what they say.
As to the missing libpng12.so library I simply installed it manually. But when it comes to lbstdc++ I do not have (as far as I can see and find) anything to install or add. Older versions are not supported by the distro and I do not want to dig too much into these compile libs since that can mess up the whole distro in a bad way.
Also, I imagine that this issue would have happened even if I had the Steam version. The steam folder do not contain these libraries so it too depend on the system wide ones.

The link you provided is essentially what I see via Synapse. But only some of them are supported or relevant to my distro. And I do not want to just install things without knowing IF it will work or what it might do to the system in general.

But my general overall view of this is that the linux version seems quite un-tested. This sort of thing should not happen. It did not happen with Transport Fever 1 and no other game I have (either from GOG or otherwise) have had this severe problems happen. So I put a rather big portion of responsability on the devs to be honest.
As far I understand it my options are VERY limited to do anything which solves the situation.
So unhappy is not quite the word I would use right now, but it will do for the time being.
In the meantime I will wait and see what happens...

OK, I can see the problem. As I don't have any experience with your distro I cannot help you unfortunately. Sorry to hear that, I know your pain. Hopefully devs will see this thread and find solutions to our problems.

Use - 'sudo apt-get install libalut0', launch from transportfever2 executable in /game directory.

[I presume libalut0 is same in Mint as kubuntu, else use 'apt-file -l search libalut' to find appropriate]

Well, some development has happened.
Firstly a friend of mine found a very possible reason for the issue I'm having. It seems the devs has been compiling with gcc 7.x and therefor create a need for CXXABI_1.3.11. They should have used GCC 6.3.0.
This is the link: https://bugs.archlinux.org/task/54944

Secondly I forwarded this information and the above, to the devs via both FB and e-mail. Since then I have received a short answer from them that they are looking into the matter (I am not the only one missing libraries we are not actually missing (in most cases)). So that is good news.

Hopefully this will resolve naturally in due time.

We will see...

Ubuntu 16.04 gives:
./TransportFever2: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.22' not found (required by ./TransportFever2)
./TransportFever2: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `CXXABI_1.3.11' not found (required by ./TransportFever2)

That's correct, as a fully up to date libstdc++6 on Ubuntu 16.04 - version 5.4.0-6ubuntu1~16.04.12 - doesn't have those versions:
strings /usr/lib/x86_64-linux-gnu/libstdc++.so.6 | grep GLIBCXX
shows GLIBCXX_3.4.21 as the highest version

strings /usr/lib/x86_64-linux-gnu/libstdc++.so.6 | grep CXXABI
shows CXXABI_1.3.9 as the highest version

Support request submitted, but yeah, the developer is going to need to recompile with an older gcc.

The devs got in touch with me. They said that compiling with older gcc 6.3 was not an option. They had to use version 7.1 for reasons. But they did give me the library file and lik to add to my system. And it worked. just fine. The game now starts and works great. So extra points to the devs. I hope they find a way to either inform customers of this particular demand in terms of dependencies. Or work around it somehow. I can not attach the packed archive since the forum will not let me.

Bother.

Based on that, I had a look and got it working myself as well.
Here's the steps I followed:
1) Download libstdc++6_8.3.0-6ubuntu1~18.04.1_amd64.deb from the download page for libstdc++6 as it's included in ubuntu 18.04 bionic. (The download link is non-obvious, but it's the red link with the text "security.ubuntu.com/ubuntu" which follows immediately after the line "You can download the requested file from the pool/main/g/gcc-8/ subdirectory at:")
2) Do NOT double-click that .deb file to install it, but instead open it with the archive manager, as we want to extract only a single file.
3) In there, open data.tar.xz
4) In there, extract libstdc++.so.6.0.25 from ./usr/lib/x86_64-linux-gnu/
5) Rename this extracted libstdc++.so.6.0.25 to libstdc++.so.6 and place it in ~/GOG Games/Transport Fever 2/game/

I'm guessing either official support for Ubuntu 16.04 will need to be dropped, or they're going to have to package this library along with the game.

According from the the devs, they replyed to me and said this, the missing file will be included in the future.

Changelog for the current release includes "Fixed compatibility problems with certain Linux distributions", so I suspect that'll be the fix. Downloading now, and will update later tonight to confirm.

edit: Yep, the game now ships with libstdc++.so.6 / libstdc++.so.6.0.25, and works out of the box on Ubuntu 16.04

Changelog for the current release includes the line "Removed libstdc++ library from working directory: Added backup in 'redist\linux\extra' (Linux)" - so it's possible things will stop working on Ubuntu 16.04 again, with this file needing to be moved over to the main game directory as a fix.