I am not sure which card I used the last time, are these sdhc-problems normal for this cam?
If you have problems with the card, try formatting it in camera (low level), then use STICK
(or your favourite method from here
) again to set it up. Make sure the CHDK folder and its content is on the big partition.
If the card is a slower one or it's filled with pictures, the camera might need longer time to scan it after start.
That initial scan may also cause the palette issue you're experiencing - CHDK only manipulates the palette in certain known camera states (and the initial card scan may be one of the unsupported states).
Once the card scan is over (the LED stops blinking), do you get proper colors for the CHDK screen elements (clock, battery, etc) with the 4285 build?