How create a custom shelf
hi,
i have some problem with creating a custom shelf. I'm only able to drag things like rotate tool and move tool, i can't drag things like slit poly tools or create a cube and how i can delete things that i drag in? 
IMG4 :bandit:
"I have a dream that my four children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character"
- Martin Luther King, Jr.