I started working with osgearth-2.9 + OpenSceneGraph-3.6.0
Under VS2015 64 bit.
I deleted all the files in the CACHE folder
I played one of the EARTH files and unfortunately I see the "white ball"
This happens only with the EARTH set in which "image driver =" tms "
The CACHE folder in this case is empty
In EARTH files where driver = "xyz" works correctly and the CACHE file is full
To make it easier to analyze the problem and on gwaldron's advice , I've made the following environment variable definition :