glad to know it works.
those steps looks correct. if you would like to simply the process. you may skip step-4 and step-5.
I’ve some comments for your question-2…
you may see the script file, apply_binaries.sh, this is the script file to apply binaries into rootfs directory.
for example, extlinux.conf, it’s copy from bootloader path and writes to rootfs folder. you may update both of them if you don’t want to perform apply_binaries.sh again. the flash process actually check the rootfs folder to include all the content for flashing your target.
in addition,
after you perform step-7 to flash the Nano, the system.img has been created for flashing. the next time you may include -r options to skip building system.img again, it’ll reuse the existing one to shorten the whole flashing process.
We tested the performance of other software on the newly flashed Nanos, and everything works so far. So we might as well close this topic. Thank you immensely for your support.
Just one more thing. We also need to create a signed and encrypted update files, to simply update the changes summarized in my above post, like the dtb to partition DTB, and the bootloader image to partition LNX, etc. So as to avoid flashing the Nanos each time, as they might be in a remote location. Of course this will be a prevention method rather than a cure. But I have created a separate topic for that here: How to update u-boot binary on the LNX partition for Jetson Nano without flashing.