raph800 startup.txt looks fine on my end -- probably is not DOS formatted, which is why the line breaks don't show up for you. Grab Notepad++ to edit it (and everything else, it's a stellar piece of open source software). Or just use the formatted version TWiST posted right there. Or grab it
here.
The difference between the startup.txt files is... the... differences between them. The parts that are different. I'm a bit confused by the question. the raph800 version sets a different machine type (machtype/mtype), which allows the kernel to know which specific code to execute. And it sets some different values in the cmdline (the g sensor has different axes than on the raph100, for instance).
Haven't tested the new build, but I have some thoughts about data connection troubles. Hint: it all comes down to APNs.
...I hate APNs.