Hi buetts, welcome to the forum !
If you unpacked the zip to your SD card properly, it should work like this:
- start camera in review/playback mode
- press Menu -> Canon menu opens
- choose the menu tab that is left most
- scroll ALL the way down (note: there's more items than fit on screen !)
- last item should be "Firm Update"
If that is NOT the case, put your card in the card reader and open it:
You should see the file PS.FIR in the root of the card (next to your photo folder DCIM and the CHDK folder)
If you don't, something has gone wrong copying - be sure to unpack the zip 'using folder names' and unpack
it to your card's root (for instance to G:\ if that is your drive letter) and not to your photo folder (G:\DCIM in this example)
There's one other frequent reason: in case you are using a MacOS computer it could be trying to protect you
from evil downloaded files, see this page:
http://chdk.wikia.com/wiki/FAQ/Mac and scroll almost to the
bottom of the page to find the "Still having Trouble ?" section
OK, that's all I can think of right now !
give it a try and let us know if you did / did not get it to work
cheers,
wim