Remove all unnecessary includes from scn file. Load just tracks, semaphores and traction. If everything is in one file, then you have to use program by @Szczawik that split scm files thematically. Excel macros by @Mariusz also have that option. Usually it makes a trick. Sometimes also few tracks have bad geometry and then after loading includes you can see them on errors list above as "line xxx; control vectors too close to one another". Ra said today that in this case you should split this track into two, but i don't know how to manualy recalculate control vectors of Bezier's curve after it. If it's nothing important, like some side tracks at the end of the map, setting control vectors to 0 also should work.
