As Andy B says - avoid running on the chines/strakes, try and straddle them.
Absolutely correct with the rear rollers too. Try and be no more than 4" from the transom. Especially if you've got some hefty outboard(s) on the back - you want to support it as much as possible.
Have the rear rollers further towards the outside of the trailer, this will benefit you in two ways: it means the rear of the boat will be more stable and also that the rear will be lower then the bow, making launching and recovery easier.
Some pics to point you in the right direction. You'll notice the front rollers straddling the strakes and the rear rollers further to the outside of the trailer, with the rollers running along the edge of the outer most strake.
All the best