Besides the usual lack of time and focus on my part, this fridge regularly shocks me with some design obfuscation. I have found (by testing the controller's speaker with a 9V battery, how ever that worked) that the logic and memory on the board is still functional.There is an issue with the mains and compressor signal leads it seems.

I made a parallel connection for the compressor and it worked momentarily before the fridge tripped the circuit breaker. I then discovered the board shorted badly but no components I could find were damaged somehow so I cleaned up the solder. 

Since then the PCB has ceased operating, I think due to a short within the fridge with the live wire (as I mentioned). When I get a chance I'm going to see if I can make another parallel for this.

At this stage though, I don't think I'm going to need to make a controller, I just need to stop procrastinating :-P