I just tried this and couldn't get it to work? Did you have a space between english and 1? What other steps did you take to 'refresh' the list? It just shows up under the challenges section in new game right?

Exact steps I took to get this working.

1. Subscribe to challenge via the workshop. Game was closed at this point.
2. Opened the game, clicked Downloads, then Steam Workshop. Found the challenge in the 'Subscribed' List... clicked 'Install' on the right-hand side.
3. Closed the game
4. Opened the FM2014 editor (Found in the Tools section of Steam).
5. Clicked 'Challenges > New Challenge > Blank'
6. Clicked 'Challenges > Save Challenge As'
7. Left everything as it was and just pressed 'Save'
8. Closed the editor.
9. Re-opened the game and went to New Game > Challenges ... Right at the very end was a new challenge called "Untitled". Pressed cancel to return to main menu. Left the game open and tabbed back to windows.
10. Browsed to the folder "C:\Users\YourUserName\Documents\Sports Interactive\Football Manager 2014\challenges". It contained 'config.xml', 'untitled.xml' and 'bottom_division_favourites_english.xml'
11. Renamed 'bottom_division_favourites_english.xml' to 'bottom_division_favourites_english 1.xml'
12. Tabbed back into the game, pressed New Game > Challenges , and it was there at the very end.

Thanks for the detailed response. I will have a go at this when I buy the editor sometime.

The database editor is free, you just need to download it from Steam Tools.

In your Steam library, click next to the search bar, where is says "All games" or "Installed", and change it to "Tools", you will see it in the list as "Football Manager 2014 Editor" :)

The paid editor operates in real-time, and is pretty much just a cheat system to edit players on the fly rather than somewhere where you create your own leagues/tournaments/challenges. The free one will more than suffice for sorting this out.

Awesome. Thanks for all your help.