[XenonSurf]

I don't know if this is the problem, but even without Real Navigation : Supermarks are sometimes reluctant to get on the map, you must zoom out the map first, place them, zoom in and then move the marks with precision. Save them in a file when quitting game from the messages pop-up window.

I always place a serie of marks for heading lines or calculated convoy positions where I put text in about spot time, speed, ETA etc. When I reload game I have all info at disposal quickly. (Without Real Navigation, I leave this one for students in Geometry...).