I had a similar problem. I set up another account to be named Administrator Windows wouldn't let me use the name Administrator, I believe it said that account name is already used,(hidden Admin?) so I named the newly created account "PC Administrator" then changed my local Admin account to local user.
I don't know if I went the about it the right (I'm sure someone here will let me know LOL) way but it works for me with no problems. I run my PC on a daily basis as a local user. All backups,imaging and maintenance I perform from the PC Administrators account.