Songbird Portable Not Using USB

I posted this on the Songbird.com website, but it was suggested that the problem was with PortableApps, so here it is:

I purchased a Toshiba Canvio Basics USB Hard Drive 320 GB, installed the PortableApps system and Songbird Portable on it, and copied all of my MP#'s to the Music folder on the USB drive.

I can't seem to create play lists that contain those songs. It seems I can only create play lists for music in the library, which is stored on computer to which the device is attached.

I want the music library for Songbird Portable to use the Music folder on my USB hard drive.

Thanks!