Terrain Builder[TB] generates "tartan" / striped layer masks from import data using high resolution imagery (1/2/5m/pixel) - IF it accepts it without giving "Default Satellite File Doesn't Exist" error.
(Can we have messages pointing to what is actually wrong? This seems like a genericly vague error message, that is quite frankly of no help what-so-ever..)
Using my map sources TB generates my layers / grid without any errors when I have 10m/pixel Sat & Surface masks - anything above this level of detail results in the "Default Satellite Files Doesn't Exist" error OR generates a map with a "tartan" effect on the sat/surface masks - which is un-usable as a terrain.
There are a bunch of people having multiple mapframe errors with the "Default Satellite File Doesn't Exist" error, or when they do actually get TB to generate layers - usually after trying with every available mapframe setting and when they hit the 2048x2048 Sat/Surf mask tile size - it results in the "tartan" effect on the sat mask in game.