If you can save the flight plans in the default Flight Planner format, the way FS Flight Planner (but NOT in FS9 Flight Planner format) saves them, then you can import them into the CDU. If they are saved in FS Flight Planner format, they need to be saved in the (My) Documents\Flight Simulator X files folder to be loaded into the CDU. I use FS Commander 9.2 which saves them in FS Flight Planner format and I have no problem loading them into the CDU.