Abyss crater - bugged - not opening and more

On some maps craters are just not opening as the requirement which is to kill specific mobs are not spawning. Well, I can live with this but when the only mechaninc in the game that you can do is this.. its painful.

And other issue which I faced.. is the narrow maps can have abyss with the right modifiers (more than 1 rare from 1 crater) literally can block you passing them through. Using shield wall need space to work. It would be great that you a bit fine tune where and how it plays.