Sample debug FW works fine, release not

Referring to this discussion before:
I have now successfully compiled sample project, modified it and it works as my exception on the debug mode in JTAG DC-ME-01-JT module.
If I now compile release FW of that project according to help “deploying a NET+OS application to a Device” and upload both rom.bin and image.bin found on release folder using ftp transfer in binary mode, my target module DC-ME-01T-C doesn’t boot in my FW but runs into a recovery boot. I can recover it back with TFTP procedure.
I even tried the same release FW upload with FTP to my JTAG module inspecting in the meanwhile serial output of the JTAG module which tells checksum correct after upload.

What am I doing wrong?

I found similar topics

were release FW wasn’t not upgraded correctly.

I found solution which requires rom.bin and image.bin to be uploaded separately via FTP; rom.bin first, then let the device boot up and secondly upload image.bin. Then the release files are updated correctly and the device boots up.

My devices have originally 6.x and my release files are in