Okay, let me try to address this big ole post bit by bit.
The screenshot at the top: It's incredible. Really, I don't have a single complaint or criticism. It's amazing.
The cliffs: I did something a while ago for my quest that (I think) is similar to what you're trying to do. Hopefully this'll help show you how to use them:
The walkability: Unforunately, the only way to make that walkable is to make a new combo that looks like the wall, but is actually walkable, and to put that on layer 0 underneath the mesh. It's kinda annoying, but it's just how ZC works.
The grid: Are you referring to the favorites combo list? It's just a place to store combos you use a lot, so you have easy access. You can kinda remove it... sorta. There's an option in ZQuest called "Use small mode". That makes ZC use a smaller, more compact editor. I prefer it honestly, as it removes some of the unnecessary fluff like favorite combos and commands and makes the editor take up MUCH less screen space. You'll probably wanna use ZLaunch though, and set it to use 2X resolution, as 1X is kinda too small.
Designing quests: This is something that everybody does differently. Me? I generally get an idea. I create a story based off the idea. As I'm developing the story, I think of a gameplay mechanic or gimmick to use in conjunction with the story. Once I have my story and my gimmick, I try to get an idea for the general overworld shape, how many dungeons I want, and what I want their themes to be. Then, I plan out the overworld on paper, start building it in ZQuest, and build the dungeons as I get to them in rough chronological order (after planning them out on grid paper).
