In my experience I do not think it is possible.

Because the audio you will get from cd or other means will be finalized and removing certain instruments will not be possible(take care of copyrights.)

If you use Music Maker you can choose various instruments and when you are done making music you export your audio in wave or other formats right? So, if you or some one else want to dismantle that to get some instruments simply not possible or that might be hardest thing IFthere is any way.

nihon94