I was having trouble getting CHDK to run on a Powershot G7. I figured it out, but here is the answer for others who search here.
The G7 has a print/ALT button in a different place than the other Powershots I have. I thought it was above and to the right of the SET button. On the G7, it's way up on the left, near the ISO wheel.
Couldn't sleep last night, so I set up CHDK by the light of my laptop. I was confounded for a long time until I got up and turned on a light.
The ALT button still has a blue LED that flashes when you start CHDK, if you pay attention better than me.
Once you find the ALT (print) button, CHDK works like always.
