On the BlueTooth Film, you connect the BlueTooth TX and RX to the Flex Connector pins PB0/PB1. This is good for most, but means I must unplug serial link to PC (programmer) in order to use BlueTooth.
I;d like to see you put “Solder Jumper Pads” on the BT Module to allow the option to connect RX/TX to PB2/
PB3. This would allow users to use SoftSerial driver connect BlueTooth and use the UART port to communicate with PC or other device at the same time.