I think we should test, I'm going to post a scenario, give me some time.
Not that it will do any good to VS, it is not in developement mode, so anything we find will make it's way into VSF, not VS.
The topic is dear to me so let's collaborate and identify the issue...
More to come shortly,
So, I think how to do the first test is to be on lattitude zero and longtitude zero, this is where I will position my boat and anchor it (to avoid guess sailing the lops).
I'm here, place this in yout VS root.. (right click, save as.. it is a "cruise" to load).http://www.virtual-sailor.nl/zeroNW.def