I just got the signed bootloader to work with the single bank implementation but had to change dfu_single_bank.c. I believe the change represents a bug in the code.
In dfu_single_bank.c the size of the m_init_packet is 64. While debugging/testing this seemed to be resulting in a length error. In dfu_dual_bank.c the size is 128.
Changing the value in dfu_single_bank.c to 128 seemed to alleviate the issue. I'm not sure if this is the place I should be logging this - but wanted to mention it because googling didn't lead me to anything in particular.
I got it working with SDK10... I believe the issue still exists in the SDK11 code (the array length is still 64 vs 128 for dual), but I haven't tested it
Thanks, Paul