for me this sounds as if Remote Buddy tries to contact iTunes via 
AppleScript, but doesn't get a response from iTunes - which in turn 
will prevent the HTTP query from completing and the Music module from 
loading.

Please make sure, you don't have iTunes Preferences or any other modal 
dialog of iTunes open when using Remote Buddy's AJAX Remote.

More info on this problem f.ex. here:

http://www.red-sweater.com/blog/230/itunes-scripting-seizure

Remote Buddy uses the timeouts suggested in that blog, too, but 
they're several seconds up to a minute each as some operations may 
well take that long on very old machines.

Best regards, 
Felix