so if you want to add some new assets here's a list of instruction that virtual sun made

1.Download this repository as a ZIP file
2.Extract the contents somewhere readily accesible (i.e. your desktop)
3.Locate your World of Goo 2 installation folder
4.Find the folder named res.goo (It should be under World of Goo 2/game/res.goo). Make a backup copy somewhere outside of game, and rename the original to res.zip
5.Extract res.zip. Ensure the correct file structure: World of Goo 2/game/res/....
6.Merge the downloaded res folder into the one that you extracted from the game. You can do this by moving the downloaded res folder into the World of Goo 2/game folder. When asked, chose to replace all files.
7.You should be good to go!

link to the website https://github.com/Sun-in-VR/goo2-community-pack

and if you want to make a tutorial about it go do that

credit gose to virtual sun