Import and Vectorize Black and White makes negative.

Hi,
If someone could help with this that’d be great. I am trying to import and vectorize png line drawings (right click timeline or exposure drawing layer). Choose black and white. The preview and import both turn my white page to black and my black lines to white. This means I have no lines to speak of, just negative shapes.
I have tried changing the display renderer from OpenGL to Quartz2D and restarting. I’m not sure what else to do.
I am running Studio 5 on Mac Pro OSX 10.6, Nvidia 8800GT.

Thanks…

Well, I guess, your closed shapes are still filled with colour (white probably)…?

Open those images in Photoshop or else and delete those colour fills…
Leave just the lines (black probably…?)

Otherwise import and vectorize with Texture…

Regards
Nolan

PS:
If you like, here is an excellent tutorial by D.Nethery,
how to prepare hand drawn images:
http://toonboomcartooning.wetpaint.com/page/Importing+Bitmap+scanned++images+to+TB+4.0
(you might have to copy and paste the whole link into your browser)

Thank you Mr Scott, for your kind words. I shall check out Mr Nethery, to be sure.
My solution: I batch inverted the lot in Photoshop (so they had black page and white lines), import and vectorised and lo! They came in as I wanted - black vector lines and white background.
A work-around, aye, but functional nonetheless.