I used a kind of character editor recently ( I was quite bored with starting over and over and over the whole cyseal town just to reach level 3/4 ), which had options to change the stats of "hero 1, hero 2, hero 3, hero 4". It's based directly on memory adresses and stuff to alter the numbers... and I found out that my two characters were constantly switching position. I guess the "main" is whoever was in the upper position when you loaded the save or something like that.
