Compiling the CRYENGINE for Mono is only applicable when building the engine by yourself by retrieving the source from Github. The builds downloaded through the CRYENGINE Launcher have mono enabled by default.
To be able to use C# in the CRYENGINE, an extra option has to be enabled in CMake. To adjust this option, open CMake by either opening cry_cmake.exe (when using the source from the main branch) in the source root folder, or <root>/Tools/CMake/cmake_create_win32_solution.bat. Once CMake is open make sure the following options are enabled:
OPTION_CRYMONOOPTION_CRYMONO_SWIGOPTION_BUILD_CSHARP_WITH_MCSIf you have trouble finding the options, check if in the top right of CMake the option Grouped is enabled. All options are grouped in the OPTION group. If some options are missing try enabling the options that you do have, and press Configure button at the bottom of CMake. After configuring, it will show new values in red.
After this just press the Configure button, and if some lines are still red after configuring press Configure again. Once all lines are white press Generate and the solution file with C# support will be generated. The solution will now contain extra C# projects which are located in the CryMono folder. The CryMonoBridge project can be found in CRYENGINE/CryMono/.