@Makis: I’m not completely certain what you tried to do. Were you trying to rewrite the CMakeLists.txt of Tileson, or of your own? If you could compile the project using a unmodified CMakeLists.txt of Tileson, then have issues compiling because you rewrite it to fit what that guy wrote in the article, you are kinda on your own. If you however have issues using the original CMakeLists.txt for builing, I will gladly help you solve your issue.
Please keep in mind that this library is made to work cross-platform, which is the reason why CMake is used. I also have Continuous Integration for every platform, making sure everything compiles and unit tests are okay with each build for every system, with several compiler version that supports C++17. For the demo using SFML, I made something quick to showcase how to use the library, as there were several questions on how it should be used with a Tiled map.
As for the CMakeLists.txt for Tileson itself, I really see no value changing it, unless there is a bug with it. I’m sure many people have different opinions on how things should be done, but there is really nothing complicated with the linking of the library, and the way I see it, there is really no value added in rewriting it to do it like the guy in the article, when the options that are provided works.
You are of course free to do whatever you want with your own CMakeLists.txt in your project. If you have issues compiling your application using Tileson, I gladly help. That is, if you have not modified the original CMakeLists.txt.
If there is a bug with anything, please give me some more detailed information on what your issue is, so I can solve it. I do, of course, want the library to be as stable as possible