OK, I'll also check that, maybe loading an FS aircraft before the MD-11 is causing some problems.There has been an "advise" at various FS forums that loading directly an add-on aircraft can cause problems and that it is better to start with a default FS aircraft, then load the addon one. This is absolutely WRONG!! I don't know if other addons might require this, but the MD-11 is perfectly capable of loading directly and this is what I recommend. On the contrary loading on top of a default FS aircraft could cause problems.

Interesting... (scratching chin slowly in deep thought)