I cannot display terrain on my PMRJ GC.

Terrain is avalaible but it doesn't appear. I had some enorm latency, had to wait a few minutes before I had terrain display when I changed the terrain display type settings.

Last week, I loaded the new terrain data that I found in this forum (thank you, guys !). But since, nothing to do, I can Hit Ctrl-G or CTRL-H so many times I want, make a 2 hours long fly with "terrain" message displayed, nothing to do !

Any idea ?