What is going on with the underspeed/overspeed points penalty system? Typical scenario......I'm travelling at 40 mph and get a distance countdown to a 15 mph max speed sign. I reduce speed at the sign to 15 mph.... but the max speed indicator in the HUD reads 40 mph and takes ages to eventually reduce to the 15 mph speed........by which time I get penalised for being grossly under speed when I'm actually travelling at the speed indicated, (15 mph). Am I doing anything that is fundamentally wrong?
I don't recall there being an underspeed penalty, unless you are referring to the timeliness penalty. The only times I can remember this 40-->15 speed limit change occurring is London Commuter and the Bakerloo Line. I have not experienced anything like what you are talking about at all. Speed limit increases (not decreases) take effect from the back of the train (mostly), could this be the issue?
If you go back to this location and go to the pause screen you should see a graphical representation of the line speeds. If the line doesn't drop then it's because DTG haven't set the track parameters properly so this should be reported as a bug As you haven't specified where this is in game, we can't compare notes on our own systems but fi you could take a shot of the map location and the pause screen we can then compare over different platforms
I have also noticed that the incab speedometer doesn't always match the hud speedometer. They're about 1/2 mph off. So sometimes for example, if the speed limit is 35, and I am doing 35 on the hud, the in cab speedometer indicates 36 and I get docked 15 points for being over speed limit. So now I just make sure that I keep at least 1 mph under the speedlimit as indicated on the hud.
There seems to be another quirk to the penalty system. I've realised that going underspeed gets me a 30 point penalty whereas going overspeed only incurs a 15 point penalty. Going very overspeed (or whatever the game describes as very overspeed) incurs just a text display warning.....and no penalty points.
The speed limit is a recommendation, not a target... Simple math... Stay under the speed limit and you will be fine...
I think you have misunderstood the scoring system. You earn 30 points for staying below the speed limit. You earn 15 points for being slightly above speed limit. You earn 0 points for being significantly above speed limit. It is impossible to lose points in Train Sim World. DTG have made it like this because they do not like the scoring system in Train Sim Classic.