Ni Hao,
to download an s19 file:
start hiwave.exe in the progs dir of your codewarrior installation
under 'Component' menu choose 'select device'
then select your device
when press OK it should connect to the device through your interface.
Then under the menu which is named as per your interface select 'load'
change filetype to .s19 and open your file
Then you should get the erase and programme dialog and your done!
Regards Peg