Creating Secure Firmware and Bootloader

I am following ardupilot/Tools/scripts/signing at master · ArduPilot/ardupilot · GitHub link for Firmware Tamperpoofing.

I tried to configure the board using

python3 -m pip install pymonocypher==3.1.3.2
Tools/scripts/signing/generate_keys.py Prabhat

Tools/scripts/build_bootloaders.py CubeOrangePlus --signing-key=Prabhat_public_key.dat

./waf configure --board CubeOrangePlus --signed-fw --private-key Prabhat_private_key.dat
./waf plane --upload

after this i did “flashbootloader” from mavproxy. All these steps were completed but after that CubeOrange is not showing any connection ports on plugging in and a constant light is glowing.

Also i have some more questions.

  1. when we sign the bootloader in second command. Does it update the CubeOrange with secure bootloader or it updates bootloader and firmware while flashing using mavproxy.
  2. what if i use mission planner for flashing instead mavproxy, do i have to upload arduplane_with_bl.hex or just arduplane.apj

After all this the CubeOrange should be secured, or is there something i am missing?

Thankyou in advance.