Songbird Playlists help - Songbird, iTunes, or Doubletwist?

I recently purchased a 4tb portable drive and wanted to have iTunes on it so I could play my iTunes playlists wherever I go. The closest solution I found was Songbird. But Im having some issues. I copied the music folder ( from "C:\Users\varxt\Music\iTunes\iTunes Media\Music) to the portable drive, then installed Songbird. When I requested to "import" all the playlists from my iTunes, it did, but the source of all the tracks were still originating from my host computer (so "C:\Users\varxt\Music\iTunes\iTunes Media\Music") and not the portable drive location ("V:\Music") I uninstalled Songbird, and reinstalled it without importing anything, then Exported a playlist from iTunes as a txt file just to test it out, but when I import that txt file as a playlist into songbird, it does a milisecond progress bar thing and then nothing happens.

So, what I'm wanting to do:
Have a portable iTunes or Songbird on my portable drive with all the files on the same portable drive and copy over all my playlists from iTunes, but have it pulling from files on the portable drive.
Is anyone familiar with doubletwist? is it a better option?