Yeah i'm pretty sure the CR-3100 is working fine, since I have a small 128MB SD card that I popped in on slot 1 and it picks it up right away. Also when the psp is completely turned off and I turn it on, with that big card in, it won't even boot up, seems to be trying to read the card.
I have 2 32GB cards so I tried different combinations and no go. Also tried formatting them on the computer first. They might be fake cards, but I would think even fake ones should be recognize on the PhotoFast, since they easily recognize 32GB cards on the laptop fine.
Oh well, time to return them and get regular 16GB ones.