after I have the files in the playlist if I drop a file onto rhe program it plays then all the files in the playlist are gone? So you say hold shift then drop the file in and all the other files will still be there?
Yes. If you drop files on XMPlay's main window, those files will
replace the current playlist. By holding Shift while dropping them, they will be
added to the playlist.
Also what is the library? There is a setting auto add to library on play-I see the library file in the programs folder but it does nor get larger-how would I use that option?
See
Illustrated Manual - Library on the Support Site.