hey comet, actually your using the first of two options which is :
EXECUTE FILE Filename$, Commandline$, Directory$
the syntax for the command your looking for is :
EXECUTE FILE Filename$, String$, Path$, WaitForTermination Flag
as you can see it takes 4 paramters in place of 3. You can set the wait flag to 0 or 1. setting to no-wait means the second file will execute in the background while the first window remains active, setting to wait means that the first file will wait until the second file has completely exited. so you could use :
execute file "music.exe","","",0
execute file "music.exe","","",1
Its been a long time since I expermented with this so can remember which one does what but I think this should help you

accomplish what your after.
ya its been about 5 months but I've been busy with other projects so haven't had much time to spend in the forums lately but I believe I have time now to do a couple more db projects.