I wanted to up date you on something I have found.
I have a 2GB & 16GB card that works in Windows and formats fine. When I use it for logging the meter seems to get stuck in what looks like a one second logging mode with long blinks every second but it never logs anything. It does this no matter what interval I set for logging, how I turn off logging, how I exit the app or even if I kill the app. The meter never goes to a very dim ten second flash mode even if I hibernate it either, it just flashes brightly every second. Interestingly enough this is the same pattern when no card is installed, it seems like off as well as hibernate would be using more power since the LED is blinking brightly every second with no card.
My other 8GB card works just fine and logs as expected. When I have it installed and not logging it flashes very dimly every ten seconds. When in hibernate mode the led flashes bright every ten seconds (but is not visible in to the app as expected). Seems counter intuitive but probably when in hibernate mode not having the Bluetooth on is the big savings in power and a brighter LED is no big deal. Also I suppose the bright flash is when it is reading the ohms to see if it has been shorted to wake up the meter.
In any case I found it interesting that the meter appears to be in a one second logging function with no card or what appears to be a card the firmware does not like. I have no need for the 2GB card if you would like me to send it to you.