RobLent,
They added a bunch of new functionality for 9.6.2 mostly around being able to provision/netboot OS X devices.
With that being said I do not think that is your problem - I normally see the problem you just stated when one of my PXE services has stopped. It is very common after doing an install of PXE that it doesn't start. I would check that first. Then you could also check to make sure the C:\Program Files (x86)\LANDesk\PXE\System\images\Boot\boot.wim files exist, as this is what it is trying to offer up.
Lastly you may just want to uninstall and re-install the PXE rep. The SP didn't break anything, you likely just got a bad install that time around or a stopped service.
Peter