Looking at your mod ini file, it looks like you are treating it as if it were a replacement for the Default version, but that's not how Unreal Engine 3 handles config files -- and for good reason. If it were simple replacement, then only one mod/DLC could make changes to a particular config file. Instead, it is a merging process. There are "command prefixes" that allow adding lines to and deleting lines from the Default version. From the Epic documentation page : The full page is here : https://udn.epicgames.com/Three/ConfigurationFiles.html I really cannot express enough how much I appreciate it, that you invest your time to help out clueless newbies like me. You are really awesome. I get it now, I don't need to replace the whole file, so it's enough if the .ini has the lines I want to change and the correct character at the beginning of the line. So if I only want to add a random amount of extra Aim per level, my line would look like this with the . in front ? .SoldierRanks=( aAbilityTree=( (AbilityName="SwordSlice", ApplyToWeaponSlot=eInvSlot_SecondaryWeapon) ), aStatProgression=((StatType=eStat_Offense,StatAmount=1,RandStatAmount=6), (StatType=eStat_HP,StatAmount=1), (StatType=eStat_Strength,StatAmount=0), (StatType=eStat_Hacking,StatAmount=0), (StatType=eStat_CombatSims,StatAmount=1)), ) @2much4l1 - You mean for testing ? if I put the default into the mod with deactivated lines it might srew with compatibility to other mods, wouldn't it ?