I've had another good look at the board and its clearly been worked on previously. I removed the rom chip and the green line goes to one of the pins on the rom socket. Traces are also visibly shiny and the board appears to have been laquered.
I'll check for connectivity but where can I get hold of correct board schematics? Its a rev6.1 board?
Weed
You may not need a schematic(but you can download one), just use a multimeter set for continuity and check each trace from end to end to see if it has continuity- try and find vias or end points the traces lead to and check there. Its hard to get a good probe to register on vias since there is solder mask on them,but it can be done.
the typical repair you see there is common on the 3000t. most the time you clean and then tin the traces with solder to make sure they are intact,it may be a case that one of the repairs come loose or did not hold well.
i am guessing you will find the trace that has no continuity and repair it and hopefully you are back in business.
there is another thing that could of happened(lets hope not). acid inside the layers may have eaten something else.
i wish you luck on fixing it. a lot of persistence will pay off.
Mech