I made a copy and updated it and will probably use it too. Here's the spreadsheet if you want to check out what I changed (mainly the APR calculations and the totals, added the interest every 4 weeks):
https://docs.google.com/spreadsheets/d/1kusptEP_7cUGO7uI5vka1JaT2nTUB5ebX-zBDm75W2U/edit?usp=sharing