Hi jonas3025
You don’t have to touch any of the notes in the key editor!
If for example a cymbal sound is playing instead of a kick, simply highlight the pad that has the kick sound you like and then right click and select CUT and then find and highlight the pad that is playing the cymbal and right click again and select PASTE and now your midi file will be playing the correct kick sound.
Use the same method for all your kit pieces and once you’re done don’t forget to save your new kit as a user preset to be on the safe side! 
Hope this has resolved your issue?
Kind regards
James Colah