Im convinced there is a bug regarding burning damage as well, although im not sure of the specifics. The burning mechanic seems very tempermental to begin with.
I've had characters die several times because during real time, they start taking burning damage, and instead of taking it every ~2 seconds, they take burning tics rapidly every ~0.5 seconds and this lasts until they die. Its impossible to heal through, and it doesn't go away after 2 or 3 'rounds'.
I do agree, something seems off. It is playable as is, but as you say it seems some un-explained happening occur. Like massive spikes of quick burn damage. If that is wanted, then the damage #'s should be lowered. I can get into big battles and in a few turns the baddies just explode without clear reason.