not able to save a flight plan in FSX

Hello,

it is a wonderfull tool, but I can not save a flightplan to the flightplanfolder of FSX. My workflow: I create a flightpan with SimlauncherX add him to the choosen flight (it shows requested flightplan with the name).But I am not able to save the flight plan, the button in the contextmenue is inactive  And so if I start the choosen flight, there is no flightplan to load in the FMC etc....Whats wrong?

Thanks for help!

Klaus