@Tryzub Hello, Windy Maps use base maps from OpenStreetmap.org, so if you would like to add a new route or correct some mistake, please visit OSM directly, you can make those changes even by yourself. ~ Cheers
The mean wind in a layer from surface to 450ft height above ground level.
With the slider at 6400', you see winds at a layer aprox. 6800 ft.
Generally model's winds for your location (elevation 5800') are 400ft off.
As you go upwards, this difference decreases.
About grey lines, please read