Doran, the boat is Not suposed to be resting on those center rollers, they are there to protect the bow of the hull during loading, the center of those cross members are the weakest link in the trailer.
When I got the new scimitar, the trailer was not road worthy, because the boat was riding on those rollers, the cross members were broken from the main frame, Roger had the trailer repaired at a boat shop before I brought it home from Colorado, since then I have raised the bunks 3/4 inch to where the boat is surely riding on the bunks.