Suggestions to improve Essentials


dabbling in game design
I've already added a couple of scripts for this to the next version of Essentials. They do what you describe for "Distance", but the x and y ranges are separate values so you can set them separately. "Range" would be the same as "Distance", I think, so long as the event started off in the middle of it (I don't know why you mentioned a triangle).

Events on water can already only move to other water tiles. This was done because of swimmers.

There's this and this, although I agree that the relevant information (and more) should be gathered in a single place for easier reference.
Since you agree that relevant information should be gathered in a single place. Would it be okay if I made a free PDF tutorial to go along with Essentials? I thought it would be appropriate to ask before just getting to work on it, in case you already have someone else doing that.