I am surprised Dave missed the bad layout on the ReflowR pcb:
If you look at the mains side, the distances between the traces aren't anywhere near where they should be for 230V.
The middle pin at the mains connector is typically the earthing connection. The area around it is used for heat dissipation of the triac, so it is connected to live. So we have around 0.4mm clearance between earthing, live and neutral. It looks like the whole pcb was flood filled with one signal without setting up the correct clearance rules.
The isolation between mains and the low voltage side on the pcb is ok, so the small clearance may not be dangerous for the user, but I still doubt it will pass safety requirements for some countries.
Also using thermals for a pad used for removing heat from a device isn't the best idea.
Before connecting this device to mains, I would verify if the case is properly connected to the earth wire just in case there are some other problems!