Edgefinder Probe problems

I recently received a script from Evann Dalton using a modified script from Allen Massey for finding all 3 edge zeros with an edge finder plate.
I have had problems getting this to work and emailed him for advice. The email reads

"I spent the morning wiring up the edge finder to use this script, but the first problem is that I am using Mach3 in metric, so I presume I will need to alter several entries in the script to suit.
As I am not familiar with the language can you tell me which entries need to be altered please.
Secondly I have wired up the edge finder directly to port 13, which was my only free input port, but nothing lights up on the diagnosis menu, so it seems there is no contact.
Do I literally just wire my twin flex to the port 13 pin, red to pos and black to the neg part of the pin? I have seen some videos which suggest I need to apply a 5v supply to the probe wire and
wire a resistor and capacitor to the ground wire.
Ive configured the probe in “ports and Pins” and applied the changes as described.
Whilst trying to solve the issue I changed the probe “active low “ box back to “active high” and the digitise led then shows green constantly. does that help?
I’ve also traced my wiring back to the breakout board and all seem sound.
Sorry to trouble you, but frustration is setting in and I must be very close to getting it working."

Evann suggested I contact a help forum for advice, so if there is anyone out there who is familiar with the Allen Massey edge finding code and could help me to finish the project I would be most grateful.

regards
Ian Parr