Split the Welsh Premier into 2 divisions of 10 with the Cymru Alliance and Welsh League Division 1 set to playable with Promotion and Relegation in operation between the two levels, Cup and League Cup as normal.
Once I find out how to do it - I'll also include an additional tournament based on the old style Welsh Cup - which included English clubs from the Border Counties of England.
How to install:
* Place the .xml file to the folder My Documents\Sports Interactive\Football Manager 2010\editor data. In case you can't find this folder, it's within the folder that savegames get saved.
* When starting a new game, in the "Choose Database" box, hit "Change" at "Editor Data Files" and then OK. Select the file you placed to "user data" folder. Click "ÎŸÎš".
Thanks to Worcester City Res. at SI forums for creating this!