1. Install gcc, gdb, cmake, and Qt (qmake) from your distribution's repositories.
2. Start Creator without existing settings.
3. Go to "Tools" -> "Options..." -> "Build & Run".
4. Check the contents of the tabs "Compilers", "Debuggers" and "CMake".
   The installed tools are listed in the "Auto-detected" branch of the tree view.
5. Check the contents of the tabs "Qt Versions" and "Kits".
   The auto-detected Qt versions and the default kit are listed in the "Manual" branch of the tree view.

First of all, the behavior should be consistent for all tools. Automatically detected tools should not be listed under "Manual". Maybe "Auto-detected" should be renamed to something like "Defined by Installer" or there should be three categories.