That's right, even without Real Navigation the trail lines are not shown by default for realism purposes, it would be too easy to immediately plot a course to intercept.
And if you play with Real Navigation you get no markings at all, you must calculate yourself...
But you can play without Real Navigation and make appear the complete lines with the OFEV if you like
Tip: Get familiar with 'Supermarks' because once you leave the game all you have marked normally on the map will disappear. Supermarks can be saved and reloaded.
Cheers, and Welcome To Subsim
