Editing the sortitoutsi Data Update files

Is there a simple way of understanding how to edit these data files myself? Basically I want to edit the latest files so I can amend some players potentials (mainly youngsters who I want to improve - Rashford, Dembele, Sanches for eg).

I've edited the standard FM15 database, saved as under a new filename and then when I start a new game clicked this on in the editor data files along with all the sortitoutsi files. The players are all working but the promotion and relegation editor data files aren't. Am I doing something wrong? I don't' really understand the option to merge database files either?

Is there an easy way of getting all the sortitoutsi files into one simple editor data file including my amendments?

Cheers