No, you don't have to show your game to GG. But, you might want to anyway - they're game publishers too, and they might want to publish your game.
You do need to buy a license before you can publish. That is, you can't publish anything you make with the free demo. But once you do buy the license, that's all you need to pay - there aren't any royalties or other charges beyond that.
Torque 3D Owner Sherman Pendley
You do need to buy a license before you can publish. That is, you can't publish anything you make with the free demo. But once you do buy the license, that's all you need to pay - there aren't any royalties or other charges beyond that.
Here's the TGB license.