Hi Peter, FireCapture will capture the raw8 (undebayered) images by default - in fact, this is the best way to capture the images to file, and use something like AS!3 to debayer them afterwards.
Of course, it is best to see the images in colour on the screen, so there is an option to display the colour image on the screen. It looks like a 9 box colour grid, check this and the colour image will be displayed. I would strongly suggest you watch some of the tutorial videos on the FireCapture website to learn the software