I wasnt completely sure of how to do it, or what the diagram meant..
Does it mean: just 4 wires are connected, 3 of which need diodes, and a few pins at each end are merged (?) [can those be merged for sure in the middle, or is there a possibility of the device needed them merged only at the ends?].
I thought it would be easier to trade for from someone who has made a custom serial cable before... and has spare parts, I dont have spare serial cables etc..
Im not sure if double shielding would be necessary or not (for a graphic tablet)