I have just purchased the game and love it. I am having some difficulty understanding choosing the traits for your Heros when you can upgrade them.

When the screen appears with the choices for a new trait a lot of buttons are highlighted. For example level 1 and 2 of a particular magic branch are lit. Can I just go right to level 2 for my first choice or do I need to go in order? also some traits I have already chosen are still highlighted. How do you know those you have already chosen versus the ones you have not chosen?

Thanks.