RiuKoki

What mods are you using? And what are your launcher settings?

Its not that hard, depending what you want. You could just make a potato and add a rune spell to it with no textures. Or scrypt the whole thing into a spell that drops a potato at the location and the invisible rune. Easyer sead than done :D

Are you using any mods that might affect fire or casting spells?

Try uninstalling Grass on Steroids and reinstalling it.

Are you an adult?

Uninstall, re-download, install, open. Should work then. Maybe your firewall is blocking it.