[Project] G80-2550: how to add some extra keys

[7bit]

I try to find a way to add some extra keys in the cursor area of my G80-2550.

There are 4 blind caps underneath them, there are the holes to solder in 4 extra switches (like the 2100 has).

I've tested these, but connecting the pins from below the PCB has got no effect.

Has anybody got an idea how to make these keys work?

Thanks!


EDIT: This is now obsolete, because I've discovered Tipro.