I just noticed that the plotted course in game UI is not accurate (not still) and it moves from one side to another if you dragg the boat to left and right of the game interface.
I noticed it because I was pointing to the cape at E of Honolulu coming from North without fixed TWA to be more accurate. If I drag the boat to the left of GUI fully zoomed (or close to fully zoomed, as you should do to be more accurate and avoid running aground) it closes to land, if I drag it to the right of GUI it keeps a bit more far away from land.
This can be an issue if you need to keep safe distance from land and you have your boat (in this case) to the right of your UI.
I'll try to test it in another situations, but for the time being it may be safer if you guys are aware of this in order to avoid running aground, as the plotted course seems to not be accurate.
have safe roundings.
Nuno