You are trying to put together different recommendations without understanding
of what you are actually doing. The result is that the both approaches fail.
Your IVT tool fails because you are giving it a wrong file as the bootloader
image. Besides that, you are generating an S-rec file which is useless in your case.
Follow the steps specified in S32DS User Manual strictly. If you want to
follow the alternative approach, contact the person who have given you that
sequence for further guidance. There is nothing wrong in it, but you have to
follow it correctly.
And last, but not the least: Study your processor Reference Manual to understand the
role and the logic of the structures you are trying to manipulate: IVT, DCD, application
image, as well as the boot flow. The references to the related sections of the document
are given above.
Best Regards,
Platon