> I'm interested in editing the downloaded rootfs image and then creating a
CF
> .img file- just like the downloadable one, for the soekris net45xx boxes.

I described how I did exactly this, including scripts, here:
http://m0n0.ch/wall/list/?action=show_msg&actionargs[]=1&actionargs[]=46

This was a while ago and m0n0wall has changed a lot since then, but I'd
guess the scripts still work.  Please let use know if you try them and they
do.

Good luck!

cheers, michael