here u can build all in hl2.
To make this you must open the gmodplus15_2 after that gmodplus and now u must copy the files in your gmod9 folder.
Then u open gmp_spawnicons and make the same.
Now u start your game and server and u see in the main menu the button "gmod+".
You can use him on your server or another server ^^.
Or you use the readme