Range of valid values for then horizon levels

[Extranjero]

What is the range of valid values for then horizon levels?

I changed the horizon level again and again (with the same pic) but I don't notice any change in the output: sunset happens always on the same place nearly in the center of the pic.

[Mallorca]

When you change the horizont level, of course the "way" of the sun is also changed. The radius is different between sunrise and sundown and also the high of the sun at high noon.
Werner