Not sure where to put this. After a FSX re install everything is as smooth as silk except for a problem with textures when dragging instruments to a second screen

 

eg. pmdg 737, in flight I drag the FMC as I always have done to the second screen to use it however now when I drag it the FMC just turns Black but when I drag it back to the primary screen it reverts back to normal

 

anyone have a fix for this?

turns out I can not save my fsx.cfg even with UAC off in Win 7

 

so it keeps reverting back to default and highmem fix is gone hence the texture problems

 

How can I permanently save the .CFG??