thats a long unnecesary wayTo create a custom Hero you simply have to go to Object Manager, select New Custom Unit, name it, select a Hero-type unit from the list and you have yourself a Hero unit. Now, in order to change it's looks, you have to find the line: Art - Model File and change the model to something you like. Don't forget to change the lines Art - Icon - Game Interface and Art - Icon - Score Screen to fit your selected model.
Now, to make a Hero into a normal unit all you have to do is to select New Custom Unit, name it, select a normal unit (not a Hero) from the list and then change it's looks into a Hero. Same 3 lines should be changed as above ... though, if the unit is not a Hero ... it doesn't make much difference does it? (Score Screen)
Spoiler should explain some basics ... and also it makes it easier to spot the lines that need to be changed.
Kiddo.