I am fairly new to Trainz, and I see that this thread is quite old. I keep getting this message, despite a lever being visable and being able to 'move it. I have also deleted the junction and replaced it with a new one. I now get a missing lever message  for the new junction too. clearly I am missing something. If anybody is still watching this, could you give me some advise please.
		
		
	 
Welcome to the forums and to Trainz (T:ANE). Missing levers are something which appear from time to time either with actual missing levers, or if the lever is not placed where it should be.
What you need to do is exactly what you did in some cases, while in others simply moving the lever closer to the middle of the spline point ensures the lever is in place. Usually if a lever is off kilter, it will show only red arrows instead of red and green arrows. There are cases too where clicking around will sometimes cause switch levers to disappear. In cases like that, you need to add in the switch lever again.
When you've fixed your switch, I recommend testing it by placing a consist on the tracks and dragging it along towards the junction. If the switch is set for the tracks to point left, and your train swings to the right, check that the points are not curved or twisted. This happens with spline tracks as the points may twist a bit. Sometimes placing a spline point before the switch points and then straightening the track spline in between the spline point and the points, will help with those situations. In others, however, the only solution is to rebuild the switch.
I find that placing a signal before the switch and then placing a locomotive, all while in Surveyor, will help with switches as well. If your signal changes aspects, with the locomotive at the signal, then the switch is working. If it does not, you need to fiddle with it a bit more.