Dear @AiLux,
Just as a check, the Toradex Easy Installer will allow you to upload your custom image with your own application to the module. This was what you meant, right?
I think you may want to have a look on this thread of our community about secure boot on Apalis iMX6: Initial Secure Boot in Manufacturing for Apalis iMX6.
Please tell me if this helps.
Best regards,