Jon,
I can understand your disappointment. Lots of videos out their show how easy things are, and now that you try to get into the world of LinuxMCE you see stumbling blocks everywhere.
From what you have written in your first post, I strongly suspect networking/internet connectivity problems as your main problems. There is a wiki page about the snapshots (as joshpond has pointed out already), containing a list of snapshots which have successfully completed a basic installation test done by our main snapshot tester bongowongo.
If you have chosen a snapshot that is defined as working, and you do not have success installing it, internet connectivity problems and/or hardware problems are most probable the culprit.
Unfortunately, not much we can do about those two.
If you have wiki pages that contradict each other, feel free to open a trac ticket for each of those pages, and let us know about them, or, if you can after some time, just correct the ones that are wrong.
Thanks and good luck getting the sucker installed.