I added the line var float Mass; to Actor and commented it out of the classes that inherit from actor and declare it, fixed all issues but I now get the error message: Error, Importing defaults for Actor: Changing Role in defaultproperties is illegal (was RemoteRole intended?) The thing is, I did not change anything related to Role or in defaultproperties. Also since it says Importing, I'm guessing it's some ini file.. any clues?