Hi Mardy,
I used a Modified Philips Webcam for a few years for my DSO imaging.
I have the 840k Pro II ToUcam.
To get it to work you need a Long Exposure capture program and there are a couple out there but I always found the easiest to use was 'Desire', which was designed and written purely for Modified Philips webcams.
I also have a Yahoo group solely for Astrophotography for Miodified Philips webcams.
You will find the link to 'Desire' on the homepage of my Yahoo group.
Directly under the image of Carina Nebula you will see the list of links. Desire is the 1st one, here:
http://tech.groups.yahoo.com/group/modifiedtoucam/
It is a very easy program to use.
Just enter how long you weant the exposure to be (in seconds) and go.
You will also need to plug both leads into your PC. The USB controls the camera, and the Parallel controls the long exposure
Your test image, was it totally white or totally black?