Zadoc, I sent you a private message.
I hope powering the Z4 through the p8p9 will make the X-surf work. The connectors appear squeaky clean, but better get some IPA then..
I have already tried the X-surf with my Mikronik Z2 board, but it was a no-go. Jens suggested that I get myself a Z4, so I did :-D
On the Micronik, the xsurftest would complete successfully without my BPPC attached, but that does not happen with my Z4 currently. That's why I think it could be a power issue.
For the record, my A1200 is rev 1.d4. I took it out of the box to do the timing fix, but to my surprise it did not have the 123C and 125C resistors; just clean solder points with nothing attached. Too clean for anyone to have already done the fix; they were not there to begin with.