base\data\shapesYou have to restart the game when you change certain things.
1. get print bricks you can build on2. Make new stud print3. ???4. Profit
He wants to replace the actual studs that appear on all normal bricks.
Due to a change in v18/v19, the brick textures used are now whatever the host has installed rather than what you have installed. Things like that will only work on your own server, but other people joining it will also see your custom images.
make a Add-On so you can see your custom textures