Hi,
The original Ibex Farm won’t let you edit the files that come by default with new projects. However you can freely edit files you add yourself. You can use PennController.css to target PennController elements, or you can use global_z.css to write your own general CSS rules
The jump error you encounter most likely means that you are using an old version of PennController.js. Make sure to use the latest version in your project
Jeremy