Thanks both of you for your suggestions. The other options under Options > General > Behaviour > Double-click will not work as I would like. I have tried them all as follows:
The first two options (replace) will replace one or all of the songs in the Playing Now list when somebody double clicks on a new file to add to the list. This happens whether there are currently songs playing or not.
The add to features come closest to what I want. The Add To End feature does as it says, but if no songs are currently playing, the song is added to the end of the list, and then the first song in in the list is played. The Play Now feature does also exactly as it says -- but the problem with this is that if there are songs playing and somebody double clicks on a song, the current song will stop and the new one they double clicked on will start (definitely not desired). The Play Next feature does the same as the Play Now feature with the exception that it will not stop the current playing song, but will play the new song immediately following (completely ignoring the rest of the songs on the list that were already queued up if songs were already playing). The last two items don't come close to what I am looking for. Basically, I would like an option to have songs removed from the Playing Now list immediately after they are played. This would solve the whole problem. Then if no songs were playing, and somebody selected a song, it would play that song. The way it works now, is if 10 songs were requested and played, and somebody clicks on a new song, it starts at the first song out of the original 10, making the new song #11. Basically I just want this to function identical to a real jukebox. This software comes the closest out of all I have found, but still not 100% like a real jukebox. You think these features could be added possibly?
Shawn