Abilities ordering.

Does anyone know how exactly does WC3 order the abilities on ability roster?

When a unit has 8 or more abilities, with some assigned to the same place, how does Warcraft choose which ones take which place?

If i have 4 hero abilities and 4+ non-hero abilities, is there any way to make sure that hero abilities will always be seen on the bottom row of ability roster?

If I were you, I'd experiment. Try adding hero abilities first, and then unit abilities second, and vice versa. I don't know which has priority or if one does have priority over the other, but that's the approach I'd take to finding out.