Struggling to get PSU Control Plugin to work

I'm struggling to get the PSU Control plugin working and looking for some help.

System Details:
I'm using a Octopi Version 0.18.0, running on Raspberry Pi 2 Model B Rev 1.1
octoprint.version : 1.6.1
PSU Control (1.0.6)

I'm basically finding that the system isn't switching the Raspberry Pi pins on and off.
Wheh using Pin 3 (GPIO 2 SDA) for my trigger for example it always reads 3.3V, and toggling the lightning bolt in OctoPrint does not switch the pin off.

Other pins have the opposite effect where they are always showing 0V regardless of toggle position..

Most instructions state to set the GPIO device to "BOARD" but I don't have any options in the drop down menu.

Here are my setting


My sensing is set to internal, but I can't show it to you as I'm a new user.

Does anyone know where I'm going wrong?

Sounds like you are using GPIO 2, not 3. In red above the setting there it says to use BCM numbering, not BOARD.