I downloaded the editor from Steam, and made a club and then made 11 players to put in it. When I started a new game and clicked on the squad, only 4 of the players I had made were there, and all of the rest were automatically made by the game itself. I've tried changing their age and contracts etc. but nothing seems to work, but the same 4 players are always there, just not the rest. They all have the same reputation and ability, so I don't think it could be down to that.