That thing with the BMPs has nothing to do with this problem.They're normal fs2 files,I can open them with FRED and save without problems,but I can't import backfgrounds from them.
They don't appear in the mission simulator list....
I noticed that i use two different builds of FRED(one here and one with another computer).The second one doesn't have the "player under AI control" in mission specs and "import background"in background.That's strange because I was sure that I'm using the same version.
I can open with this computer's FRED missions from the other one but I haven't tried the contrary.Also,a mission transfered from the other computer is showed in the list.
Another thing,slightly offtopic:I often listen USilv beam loops and Sath Sbspc ones when I play,when actually there are no Jugg/Superjuggernauts...