Easy fix: Just use the packer to remove mods, delete data folder, grab the newest tiara from this thread, use data packer to get that running. Repeat each time it breaks. (It usually won't break very often, and if it does, shaggy here loves to spam us with updates, so by the time you've noticed it's broken, he's already got the new one ready)
Or, you can read some guides on how to fix errors, and how to make modifications (I recommend starting on mine) then find the specific file that isn't working and remove it, or repair it yourself, and update it to work.