I will try again:
Someone can tell me why my Mac can't see the partition (FAT32) with CHDK and pictures? when the G11 is directly connected from USB?
The USB connection is PTP, it's not a filesystem and doesn't have any concept of partitions. What is shown over USB will be the same as what the camera sees: If the large partition is what the camera saves photos onto, then that's what will be shown. Note that there are issues listing/transferring raw and DNG files over PTP, which are completely unrelated to partition size.
The only way you could end up not seeing the right partition is if you were loading CHDK to shoot, and then not loading it when you connected the USB.
edit: Reading your post above, it sounds like this is what you are doing by locking/unlocking your card. Solution: Don't do that.
CHDK hides the lock status, so whatever your problem is seeing photos over USB when CHDK is running, that isn't it.
Plz don't tell me to use a card reader, i want connect my G11 to my Mac USB port and get my pictures with Iphoto.
Tough. I'd suggest using card reader, especially given that you are using an OS that actually supports multipartition cards.