Background in case it matters - skip to next paragraph for just the question.
I finally figured out why my HP laptop wouldn't boot from the net, some kind of problem with the nvidia drivers or the xorg.conf. I decided to go another route and installed LMCE on the local drive. It simply will not boot from DVD so I installed Kubuntu 7.10 from CD, then linuxMCE 0710. Still no love with nvidia, but changing it back to the default xorg.conf from the Kubuntu install got the screen to come up and work ok. Apparently it is supposed to detect an existing core and do a MD only install, but it didn't, it installed it as a core/md. Fine, whatever, I booted off the net and from a text screen I logged in, mounted my internal drive, and copied the working xorg.conf which allowed me to go through the setup wizard and get a working (UI1) MD with full access to the media on the core. Finally, the almost to the bare basic functionality that I need in order to actually use LMCE for now. In trying to get my streamzap remote working (why is such a common remote not supported by default???), I rebooted the laptop. No joy in Mudville, the laptop starts to boot off the net, PXE messages and such, then comes up with "booting from local disk" and proceeds to boot from the hard drive into a core/md setup with no access or connection to the real core or the media on it. I'm not positive, but I'm pretty sure I rebooted it at least once after going through the wizard and it came up clean with a connection to the core and access to all the media.
Why is my laptop that WAS booting a MD and connecting to my core now switching to booting off the local disk after it starts booting off the net? More important, how can I get it to boot off the net like it was before?