Debugging Custom Layouts?

[prize-goof]

Is your feature request related to a problem? Please describe.
A js file runs fine on node.js, but does not work as a custom layout of Amethyst. No error messages are provided.

Describe the solution you'd like
Provide a log of error messages. (Is it already provided?)

[patmuk]

+1 - how can we debug a custom layout? Any console.log possibility or dev tools? Enabling layout debug did not change anything for me.