RadEditor does not offer resx localization for the following Track Changes strings "Inserted by ", "Formatted by ", "Deleted by " as well as for the strings in the Comments dialog: Title, Save, Cancel and Edit.
Don't forget the "title" attribute of the "span" tag for the changes, and also the terms: "Remove All Comments", "Remove All Changes", "Accept All Changes", "Do you want to proceed anyway?", "No changes has been made.", "Changes successfully executed." and also the button labels "OK" and "Cancel"; this terms are shown when the user fire some of the functions: "AcceptAllTrackChanges", "RejectAllTrackChanges" or "RemoveAllComments".