The problem you're experiencing is not due to the bridging of the points on the mb that allow for flash writing--if you hadn't done that properly it wouldn't have gotten as far as it did flashing.
What's causing your problem is that your modchip isn't entirely disconnected when you try to flash. Check to make sure the appropriate wires are disconnected, and if it still fails and you have a socketed homebrew chip, pull it out of the socket and try again.
If you still have the problem and you have a homebrew mod, it's likely you still have the wire which connects point 32 to another point on the mb connected. If you don't disconnect this wire, you will have exactly the problem you're getting (where it writes part of the flash and then fails).
Basically the secret to getting the flash process working is to get xflash to the point where you pick the bios image, and then make absolutely sure your modchip is disconnected, as well as any other connections (like the wire i mentioned which connects two points on the mb) are off. It will definitely work then.
Good luck!