Remove competition winners/history

Hey folks!
I've been playing FM20 with the following editor:
https://www.fmscout.com/a-fm20-database-england-lower-leagues.html

I'm now wanting to play it with no previous winners for the FA Cup, Carabao Cup, Champions league & Europa cup. - I've used the FM Editor to modify this, however when it comes to loading the game I keep getting a crash dump error or another message stating the file needs testing & verifying in editor.

I've also tried editing the default v20.4.0 update, but the same issue occurs.

Any help would be muchly appreciated.

As far as I know (I'm no expert and my experience using the pre-game editor is very limited), you need to test the save within the editor first. There should be an option to test something (rules perhaps?) in the dropdown menus in the top left corner. I could be wrong though - I've never really bothered with the editor previously.