I did check with authorities before making my own checklist. They told me they are absolutely fine with personal checklists, as long as it contains only additions for cockpit procedures and you carry the original POH and checklist on board. At ramp check, they are only interested in the original ones. I even translated my original POH and made two personal copies to stick in the plane for friends unable to read english. So, personal checklists and POHs are just like any other novel book as long as you have the original documents handy.