Really not sure if these have been mentioned before or not, if they did then I apologize, but these are detractors I found while using the engine:
-The ammunition you have on you when you die stays in your inventory when you respawn; if you pick up a pistol with 10 bullets, then die with it, when you respawn and pick it up again you will have 20 bullets
-Enemies can occasionally chase you in their hurt state, this happens by default even when creating them with the in-engine editor. The basic FSM for enemies from the manual is even worse, enemies just keep walking around with idle, attack, and hurt frames instead of properly reacting. I managed to sort of fix the hurt movement by making them default to idle rather than chase upon getting shot, but the rest are still a mystery to me. I understand the states are adjustable and with some work, this could be fixable by the user, but still, tighter, closer to default in-engine behavior from the get-go would be preferable for editing.
I really hope to see these issues resolved, I love this engine so far and these minor issues are the only negatives I can even think of.