I can't help with that, because I've never done anything similar.
The one with "(install)" will likely run the install instructions from CMake which you probably don't need to do (but it will likely run all the stuff from the non-install target first, so there wouldn't be much of a difference between the two targets).
I rarely touch the gui builder on Windows, and the way I develop it on Linux isn't usable for you, but what I usually do on Windows is to just run CMake in the TGUI root folder. Not via Visual Studio, but by just using the CMake GUI and setting the source directory to the TGUI root (and a build folder to a new directory). As generator I select Visual Studio. After pressing configure, setting the correct values (e.g. SFML_DIR), pressing configure and generate, you can open the project created in the build directory (from CMake with the "Open Project" button).
This gives you a VS project that builds TGUI and the Gui Builder. In the Solution Explorer on the left side in VS you can set the gui-builder project to be the active project so that you can run it.
Unfortunately, because I never optimized for developing on Windows, the gui-builder target isn't actually designed to run this way out of the box. If you link dynamically it will complain about dll files, you have to copy them next to the gui-builder.exe file that gets created in some subdirectory of your build folder. Even when the gui builder launches, it will immediately terminate. This is because it can't find its resources. You have to also copy the "resources" and "themes" directories, that you find in the gui-builder directory (in TGUI root), next to the gui-builder.exe file. After that you should be able to correctly run the program from inside VS.
Edit: I'll have a look at your PR tomorrow btw.
The one with "(install)" will likely run the install instructions from CMake which you probably don't need to do (but it will likely run all the stuff from the non-install target first, so there wouldn't be much of a difference between the two targets).
I rarely touch the gui builder on Windows, and the way I develop it on Linux isn't usable for you, but what I usually do on Windows is to just run CMake in the TGUI root folder. Not via Visual Studio, but by just using the CMake GUI and setting the source directory to the TGUI root (and a build folder to a new directory). As generator I select Visual Studio. After pressing configure, setting the correct values (e.g. SFML_DIR), pressing configure and generate, you can open the project created in the build directory (from CMake with the "Open Project" button).
This gives you a VS project that builds TGUI and the Gui Builder. In the Solution Explorer on the left side in VS you can set the gui-builder project to be the active project so that you can run it.
Unfortunately, because I never optimized for developing on Windows, the gui-builder target isn't actually designed to run this way out of the box. If you link dynamically it will complain about dll files, you have to copy them next to the gui-builder.exe file that gets created in some subdirectory of your build folder. Even when the gui builder launches, it will immediately terminate. This is because it can't find its resources. You have to also copy the "resources" and "themes" directories, that you find in the gui-builder directory (in TGUI root), next to the gui-builder.exe file. After that you should be able to correctly run the program from inside VS.
Edit: I'll have a look at your PR tomorrow btw.
