Boss DM-2 PCB problem

I want to build a Boss DM-2 pedal. It had 4 versions. I want to build the first one that uses the MN3005 chip. A PBC is available to order for it online. I checked, and it perfectly matches that of the original pedal. Except for 2 components. An extra diode (D6) is added, that was only available in the original pedal in the last version, but not in the first. And annother component referred to as CF is added to cable soldering points 8 and 10. This was not included in any version of the original pedal PCB. Why were these mods added to the copy PCB and how much is their value?

I drew these mods onto the schematic (the D6 is added in a way that the connection between C38 and R27 is broken, and the D6 is inserted between the two: