So it took a while, but just a couple of events and actions in a specific order made bullets only shoot once per click, to prevent spamming. Also, ammo has been pre-introduced (with a set amount of 64 bullets per game, obviously will soon allow pick-ups). This is the enemy glitch: what happens is that when wandering, whenever they change direction they seem to jump places! Maybe wandering isn't such a good idea for now.
Anyway, stay tuned for more development updates.