Hi Michel:
Although in some cases one may be able to alter or even apparently 'stop' display of certain Ultimate Terrain X ( aka "UTX") features by un-checking layers in the FSX menu GUI for Scenery Library, there may be
other files placed by UTX in 1 or more of FSX's own always "active" sub-folders which
substitute for default files ...which may
not be affected by changes in made in the FSX Scenery Library GUI.
As stated in the UTX documentation, to stop UTX display, one must do so via the UTX configuration utility GUI menu, which offers a "quick disable".
CAVEAT: If one is exploring FS scenery rendering, whether for personal use, or for development of scenery to be distributed to others (and whether for free 'or for a fee'), one
must "
Read The Documentation".
By doing so, the least that will happen is one will
increase the likelihood of better understanding what is going on, and
reduce the amount of time and effort expended by oneself (...and others if one's scenery is 'distributed' outside one's own computer).
Hope this helps with the learning process.
GaryGB