It's supposed to run through the waypoints consecutively, but I find your problem interesting. If the screw is amber, to signify that there is more than 9 waypoints, it will/should automatically start the next Page. The same applies to the green light.

I don't usually click on the screw if it's amber, and here is what happens to me:

Once the L-1011 II finishes the Page 1 Wapoint 9 to Page 2 Waypoint 1 leg (91 on the FROM-TO Display), and is supposed to start the Page 2 Waypoint 1 to Page 2 Waypoint 2 leg, it reverts to the Page 1 Waypoint 1 to Page 1 Waypoint 2 leg. When I get to the Page 3 Waypoint 1 to Page 3 Waypoint 2 leg, it again reverts to the Page 1 Waypoint 1 to Page 1 Waypoint 2 leg. This occurs for each new page in the route (up to 6 pages for me so far). The L-1011 II on the otherhand, still follows the route all the way to the Arrival Airport. This happens with any route I load that has 10 or more waypoints.

I will have to test it with the green light on to see what happens.