Attached is a project that exposes the current grid/map to make it customizable. The current core Quest grid code is wrapped in a paper.js instance, which makes it impossible to customize. I basically took that code and moved it out and made it straight JavaScript functions, though still using paper.js. This means you have the power of paper.js to customize the grid.
The included "grid.js" is that replacement. And the included "grid.aslx" has replacement grid functions for the standard core ones, since they need to call my version, not the built-in version.
This sample also has some room generation code as well as an example of how to customize the compass buttons.
It's a bit "loose". I could tighten it up if need be, but I think it's enough if someone wants to take and use. I figure if you want to use it, you know enough about how to code that you can integrate it properly.
Ask if you have any questions.
(The main "game" file in the zip is MapTest.aslx.)