Building on the last success with the additive blending, I've implemented flame areas that can be switched on and off with a signal.
Need to see it in motion to get the full effect:
Each one covers two blocks and they are placed with the editor like normal objects. They can then receive signals so the above is just connecting a button to a splitter gate then connecting the splitter gate to all of the flame areas.
I'll make them lethal to Squishy later on as the original need for this was to be able to create large areas of the floor that you have to avoid.
Since getting this working, I've also been thinking about developing the fire mechanic a bit more. It is quite possible that some objects could be combustible and catch fire when placed in a fire source. Squishy could then carry the burning object somewhere else to set fire to another area.
We'll have to see.