Everything you should know about configuration files is contained in "
Doc/OrbiterConfig.pdf".
Texture files for planets (.tex) aren't referenced directly but their names are taken from the "Name" defined in the configuration file. They are directly in TextureDir or HightexDir ("Textures" and "Textures2" by default). Similarly is for meshes of bodies using "MaxPatchResolution = 0", so in MeshDir ("Meshes" by default), with name defined in configuration for that body, but there you can use your own texture name - i.e. texture is defined in the .msh file.
That's how it looks for textures of planets you were asking about.
Something more about configuration files:
Configuration files for systems are referenced by a scenario file. They can be placed somewhere in ConfigDir of Orbiter ("Config" by default), so even in a subdirectory of "Config" (in scenario file their names define relative paths to the configuration file from ConfigDir).
In system configuration, star, planets and moons are referenced by providing relative paths to their configuration files, but while next defining moon of that planet, you use planet's name then, and not configuration file name (which you can name differently). For example:
Code:
...
Planetx = [<subpath_in_config>/]<planetx_config_name>
<planetx_name>:Moon1 = [<subpath_in_config>/]<planetx_Moon1_config_name>
...
Configuration files for planets can define non-default paths for markers or bases, but data files for planets are looked by Orbiter directly in the "Config" (ConfigDir) directory of Orbiter (they can't have different location at present).
