Yep, Robert, your backup utility is more complex - it covers all pilots and WOFF settings. However, my simple pilot backup does not need any user input - it does all its work in background every time a mission is saved in ME. I added this feature to ME, because I am really lazy man and I did not want to run a complete backup utility before each flight wink . Also, I experience very often "underground" flight phenomenon - almost every first mission a day, so this pilot backup is very usefull.
BTW, I suspect this error may have something with slow (pre)loading of some resources/libraries during first CFS3 start, because it happens (to me) only at first mission after WOFF start.