This is the basic case as the dark brown border should be at the corner edges and the rest expanded so the the mountain ridges fall at the mountain ridges. In the normal course of things a scaling of ,8 or point 0.85 on x and y in that texture and it would fit perfectly on the mountain ridges as well as the corners. instead I trim it in Irfanview and reupload it several times till it fits.
As noted the percentages are different for different size meshes as the sides and bottom ring of faces are one face each to provide visual closure even though they are not seen much in use.
I also have usually many different color schemes that all are interchangeable as they fit to one another as you can see in the ones for sale in Kitely
This is what that Rift valley landscape was like as it left Blender
Edit - I am reworking and re-uploading these two files of the Rift Valley, and Meteor Crater before upload so they wll hopefully both look better now.