Did you dl and extract the rar pack? In the folder jmkgTMCmod you will find the Garmin_Week_calculator_TMC_MOD.xls. In regard to your first question, i cannot explain it any better than Caty has. There is a 'how to' text file in the folder which is basically the same instructions anyway. It should be self-explanatory once you have looked at all the contents of the folder.
Bookmarks