Not a question. Let me know about your ideas, for sure! For making an engine like this, while I have a lot of discretion for random crap, my main philosophy is to not add anything unless:
It would be useful in 2 or more possible games.
Someone wants to use it in a game they're actually making.
It excites me.
Of course, the project is open source and on GitHub, so you are warmly welcome to fork it and add your own features. I'd love to see how other people could snazz it up : )
I have an idea for a puzzle game, but it's not suited to PuzzleScript
You're right, PuzzleScript isn't a universal puzzle-game-making tool. It's best for turn-based, keyboard-controlled games where you're moving a thing, or several things around.
The editor is crazy ugly.
Not a question. If you want to try reskinning it, I'd love to see what you could do. It's all controlled in css (in midnight.css), so knock yourself out. You should work on the source, rather than the raw webpage on puzzlescript.net, which is heavily compiled, and won't make much sense.
Can I turn my games into standalone executables?
I had originally intended to make a very simple native (C or whatever) cross-platform standalone client for PuzzleScript. However, it wouldn't be fun for me to maintain two separate versions of the engine. But if you want to try to do so, knock yourself out : )
Can I run the editor offline?
You can download an uncompressed version of PuzzleScript from GitHub, and that should work okay offline, except for exporting standalone versions of the games (it has some optimizations that stop it from working when the webpage is run from your hard-disk), and sharing.
Why no music?
I want scripts to be standalone, and it's not so practical for people to write aesthetically tolerable music the same way they say edit sprites. Sorry! (Maybe a better approach would be to have a seeded random music generator like the random sound generator).