Just to say that I managed to get my Webboy up and running again using the bios code intended for the 340s8 model (Gericom Webgine - no tv output).
So if anyone gets in a similar fix, I suggest they try that bios, which can be downloaded from www.gericom.com
. (its saved on the website as an img file, so you may also need to download another piece of software to "unzip" it, so to speak).
Also, if you need bios chip reprogrammed, I used a company that you can access via this website: