I have tested this now with a MK22F51212 Tower and this MKV31. The K22 worked just fine. I basically followed the attached Demo App User's Guide using both boards. The bootloader itself flashes properly to both. I am able to use blhost.exe with both and use the get-property 1 command and get a valid response from both. The issue lies with Figure 10, Section 5.7. I set the image and offset for the two boards (I am sure to use the correct led_demo binary for the proper eval board) and upon pressing update, the K22 erases the flash and writes the led_demo image and works properly while the KV31 can not get past erasing flash and instead I am greeted with "No response packet from target device.".