bkkick: If you have the compressed image file (the lzma file) on your memory card, and you run the installer, choose the same image file, and choose the same location, it will (1) check to make sure your file is good, and if it is, it will (2) decompress the file. If the file is damaged or incomplete the installer will (2) try to finish downloading the image file then (3) decompress the file.

This will take a long time. Be patient.