Hi rodders
The kernel and core.gz are 2 separate things.
The kernel runs the show and gets loaded first. That's the vmlinuz file.
core.gz contains the file system (/bin, /dev, /etc, /home, /lib, ... ) and
gets unpacked by the kernel.
I wonder if you are running out of RAM. Try adding these boot codes:
base text nozswapand see if you get to a command prompt.