My W key is broken but I can't find a way to edit the controls to something different.
There's no in-game support for remapping keys in this game. There is an "AZERTY" feature, but it's really designed for alternate keyboard layouts.
However, you can use something like AutoHotKey to achieve the same effect.
A script such as:
...would move the WASD controls over one letter, making them ESDF instead.
Copy this into a file, and save it with an .ahk extension. You can then double click the script to run it if you have AutoHotKey installed. When you're finished playing, you can right click on the green "H" tray icon to quit it.