1.) These labels should not be translated, they are "fixed names" of DirectX. But it is also not necessary because they are just some test options which usually have to be switched on.
2.) You can tell OMSI with this option, how many tiles in each direction should be visibile. A tile is a 300x300m puzzle piece of the map!
3.) I will see that I enlarge them as much as possible for the update of OMSI.
@all: Please mind that we will release an update of OMSI when the box is finished. There will be some new language entrys. Your old files will still work, but they will be not complete because these new entries will be missing. So you then have to create updates!