1. If I understand correctly, stock samsung recovery (3e) looks for signed zips (signed by samsung). So either this is writen for older recovery (2e) which may have allowed unsigned zips OR stock recovery refers to something else (thats not from samsung)
2. If my understanding is correct, there is a separate recovery partition which holds its own recovery kernel separate from the normal boot kernel. In this background, what does flashing insecure kernel means? does this procedure replace the main android kernel? does this insecure kernel also act as recovery kernel when booted in recovery?
3. is there anyway to backup recovery partition (as far as I can think of, this may not be possible. As I have not seen any way to root SGR without installing custom recovery first. and through heimdall, I dont think a dump can be taken of partitions)