Cannot delete items from crafting tablet and more

So i was in the newest Beta of Minecraft.

I just wanted to know how to make a bamboo block (I was in creative but i just wanted to know it)

Then i put a amethyst i didnt want it i wanted to put it back and it didnt putted away. I couldnt drop it and also if i mined the crafting table and placed it new it was in there. And i critted a Zombie and my Game just crashed. I closed the game.