Maybe, is there anything to do because i have some sceneries in my fs library uncheck?
Yes, this has been discussed many times on the forum, for example here:
http://www.fsdreamteam.com/forum/index.php/topic,9848.msg77524.html#msg77524Turning on/off FSDT sceneries when flying it's a total waste of effort, because we ALREADY do memory-management for them independently from FSX, since 90% of the scenery is not made using .BGLs files, but with 3d object we create and destroy on demand. When you are flying outside of the area of an FSDT scenery, none of your VAS is taken, even if you enter it and the exit from it, all of it is reclaimed.
Because of this, the Addon Manager doesn't react to changes in the Scenery Library automatically, the active sceneries list is read only when FSX starts, which also make it more efficient, so it doesn't have to check for changes in the scenery.cfg while FSX is running, and it doesn't have to re-scan the scenery library when you change it, and it does this BECAUSE you wouldn't get ANY benefits by turning on/off FSDT sceneries while FSX is running.