In a Quest game, there's an exit that you need to go through to progess, the exit is locked and there is no way to unlock it. It seems the original developer accidentally locked it. I haven't ever made a Quest game before but I'm pretty sure I know how to unlock the exit. The problem is I can't edit the game. I can see all the files in the game, but I can't change anything about them. I can add and delete files, but that's about it. Is there any way to edit the files on someone else's Quest game I downloaded?

When a game is published, the UI is disabled and TONS of Quest code in inserted. (Not what I would call an advantage because you need the same version of Quest to run the game which has that code already.)
You can only look at the code in code view. AND, unless you know what you are looking at is confusion at best.
Quest adds its code at the start and the end of the game code which makes it so much harder to separate out.
Post a link to the game, and someone should be able to unlock the door for you.

Or you could ask the author to fix the game and repost it.

Update: I went in the code and unlocked the door. Thanks for the help.