For now, It's not required that the runner obtains the full release of the game. The free shareware version can be found on this website: http://www.carrsoft.com/ctf/capture_the_flag_game.html Where it says "Download the zip file (400K)" found here:

To run this game, it's allowed you do so from a computer already running DOS, or from an emulator such as "DOS BOX" "Dox Box" can be found here: https://www.dosbox.com/download.php?main=1

To use DOS BOX the user needs to know a bit of the operative system DOS, (tutorial here: http://www.computerhope.com/overview.htm )

But to keep steps simple, you should do the following:

1. Download game's zip from website
2. Extract zip using a software such as "winrar" or "7zip" to a folder location of the runner preference
   • note: the closest you've extracted the game to the root of your hardrive (ex.: C:) the better
3. after installing "DOS Box", open it
4. on the console type "mount X X:[file directory]"
   • note: "X" being the root of where you extracted the game (ex.: "mount D D:\games)
5. on the console type "X:"
   • note: again, "X" being the root of where you extracted the game
6. navigate to where the games executable is (capflag.exe)
   • to navigate you can mainly use the command "cd" (ex.: on the console it shows "D:\games> _" if you've left the game's folder in "D:\games\DOS\capture5", you'll need to enter the command "cd DOS", then "cd capture5"
   • "cd" in DOS stands for "change directory"
7. finally to run the game, you simply need to be on the correct directory and type the name of the executable (by default: "capflag" and the game should run on the same window as the console.