1) Connect your TomTom via USB.
2) Create a folder in the root of the drive called 'screen'.
3) Create a text file, with nothing in the file, and save it with the name 'capture'. Not capture.txt nor capture.doc.... just 'capture'.
4) Place that file in the 'screen' folder.
5) Reboot your TomTom.
6) Click near the top left of the screen near the zoom button.
You will hear a "shutter click" and your screenshorts will be put into the 'screen' folder as BMP files. If you frequently use the zoom button, you might not want to enable this.