What is the full name and version number of Music Maker are you using - see under Help, About . . .
If the options are greyed out that usually means that the timeline is not in the correct state for exporting, eg an effect has an open dialog, under the main program window, that is waiting for a response from you, the project has become corrupted, or there is something else waiting to be completed.
Try saving the project and closing down Music Maker, then restart the computer by clicking the Windows start button, Power, Restart the try loading the project again.