I put a dowel in the brooders.. they mostly play on it. Jump over it, go under it. One walks it like a tightrope. My older chicks didn't start using it to roost on until they were like 4ish weeks or so. Now they're outside, and sleep on the wood chips instead of the pole! I guess as long as they're comfy!
BBQ:
Don't worry.
Your chicks will "get it" when they get it.
It's really not important.
As stated earlier, they mostly just play on it for a month or so.