Accessibility - Prototyping Keyboard Access

Are there any interaction examples, best practices or even a components widget-library for Prototyping Keyboard Access according to the given W3C WAI-Aria Best Practices Examples ( available?

Especially navigation with arrow up / arrow down in widgets like trees, accordions, tabs.

Normally I am used to do my designs & prototypes directly in code but UX Department can´t code so well.
Therefore I want to help them out getting it done.

Thanks in advance.

Guess I had to work with a global “key down” and several cases actions. Nevertheless I am happy for any additional suggestions, scripts or hints.