Issue with modding Forza Horizon 2 on xbox

hi, i’m new here and i’m trying to mod traffic cars in horizon 2 but can’t find the right tool, can someone help me?
edit: i found the fh2 tab in the game modders, but it was unclickable, all buttons were disabled and it told me to select a profile (note: there were two tabs, ‘‘profile’’ and ‘‘garage’’), i selected mine from the flash drive and the garage tab disappeared, making modding traffic cars impossible. anyone knows how to solve?
edit 2:my bad, i realized i had to open the profile from the pc files, i did and the buttons could be clicked, but when i clicked ‘‘add all traffic cars’’ it said there was an ‘‘error related to an object not set on an object instance’’ Anyone can help me solve this?