Okay, let's go through this step by step:
- First of all, can you confirm that you press the action key when you are in the game's main menu (where you see the commands "item", "skill", etc.) ?
- Have you tested it with all other plugins switched off?
- Does your game crash, or does it run and you see the "could not read config.json" in the dev console? This error message isn't necessarily a bad thing. The config file contains the settings you choose in the toolbox, so when you start it for the first time, it simply doesn't exist yet. Although the error message looks a bit strange, I, as the programmer, cannot prevent it from being written to the console due to JavaScript and Node.js.