I have a Windows XP home edition. When you "switch user" or "log off" of your computer account, does your AMHD account list you as offline, or do you have to log off AMHD?

As long as you had checked the "stay logged in" box when you last logged in, and your computer is set to accept cookies, you will still be logged into AMHD when you sign back in on WindowsXP.