[Prefab Editor (Alpha)]

Snip.

[Prefab Editor (Alpha)]

After rereading your text and playing with Hal's editor, I am starting to think that all you want is some kind of shortcut (or mouse button) for the function of the block picker tool (see screenshot bellow). Am I right?

 

YES! Please, maybe bind it to middle mouse button? Or make it configurable? It would save alot of mouse movement! Excellent tool by the way, looking forward to seeing it progress.