- checkout project from GitHub
- extract downloaded both mingw32 openconnect archives (develop package content into cloned project root and binary package content into 'nsis' folder)
- update project submodules
- optionally initialize git-flow developmenet scheme if you like
- and switch to 'develop' branch
- start QtCreator
- create/select a session if make sense
- open CMakeLists.txt from project root
- update desired Qt 5.12 version build types and click "Configure"
- open 'Project' tab on left side of QtCreator with CMake configuration
- change
- 'PROJ_ADMIN_PRIV_ELEVATION' to 'off' because QtCreator is not able to start app with UAC (?) :/
- if you like; change 'PROJ_INI_SETTINGS' to 'off' if you want store all settings into file instead of Registry for development/tests
- click 'Apply Configuration Changes' and then switch again to 'Edit' tab on left side of QtCreator
- build the project
Optionally setup MAKEFLAGS in Projects settings if you like for faster build.