Make Logon Screen With Guest Account And Switch User Button

I'm currently administrator of a couple different groups of computers at a university, and I've been looking into changing the layout of the logon screen. I've found a lot of information, but something that I have wanted from the start has eluded me. I'd like to set the logon screen (or welcome screen I suppose) to display only one available account: the guest account that I have personalized for professors or students to use (not the same as the default Windows guest account). I would also like to have the option to switch users at the logon screen, preferably with the on-screen button that says switch users which I can't seem to get to display using my methods.

System Specs All of the PCs I am administrating have some differences... Simply put, I have a bunch of desktops running Windows 7 Pro x64, and a bunch of NetBooks running Windows 7 Starter x86. I've made my attempts on one of the NetBooks thus far since I can carry it around. On Windows 7 Starter it seems that "Switch User" is disabled, but I think it is still in the PC because when I tried a Registry Hack that hides all user accounts except the one that was last logged into, I had the option to switch users, but only when the account I last used had a password. The guest account does not and cannot have one. Anyway, the registry hack I just mentioned involves going to HKEY_LOCAL_MACHINE..... and creating a bogus key under the ProfileList key.

I also tried a similar thing to the above which didn't work, I can't remember what it was though.I have also tried hiding the default administrative account I made while keeping the other account visible, but this results in me not being able to log into that account from the Login screen, and the system will automatically login to the guest account because it doesn't have a password. Not necessarily a bad thing, but I need a way to get into the other account. This was done by changing HKEY_LOCAL_MACHINESOF... and adding the account to hide as a 32 bit DWORD. Don't hide all of your administrator accounts in this fashion, or you'll be screwed FYI.

The third thing I tried was adding an entry for fast user switching and enabling/disabling it, in HKEY_LOCAL_MACHINESOF.... and adjusting the "HideFastUserSwitching" key. This didn't seem to have any effect.I also tried various combinations of the above, but that didn't get me the outcome I was looking for either. This has all been on the netbook, but I'm looking for a solution that will work on the NetBooks and the Desktops.