Editor Utility Widget Questions

A few questions for making tools using utility widgets.

  1. How do you apply modifier keys to button clicks? For example click has one function and alt+click has another.

  2. Can static mesh thumbnails be used as button images and how without taking a separate render or screenshot?

  3. Are in editor visualizations enabled? I have a transform variable set to Show 3D Widget, but nothing shows up in the scene when the utility widget is open.

Thank you.

Bump. Would be really nice to know how to use modifier keys with editor utility widgets.