Losing Post Updates due to login requirement v.3.4.5.1

I'm having a problem with Atahualpa since updating to this version (when I tried to update to 3.4.6 my blog broke with all kinds of error messages so I am staying with this version).

I am logging in, and clicking "remember me". Even so, if I have been working on a post for some time, then click update, it takes me back to the log in screen. When I get back there, I have lost all the updates I made to the post. (GGRRRrrr!! I just made a lengthy update to my About:Blog Specs page and lost all the updates, including links to plug-ins I use, etc.)

This also happened while I was making changes to the Atahualpa theme options yesterday. It is happening at random. I hit save, and I'm taken out to the login screen where my login name shows but I have to put in my password and login again. Then the settings I just made were not saved. I thought at first they were saving upon my logging in again, but they are not.

Today it has happened twice with trying to make a new "page" for my site (re: GGGRrrr above). So it is happening at random, anytime I try to save any changes. This is all new since upgrading yesterday from version 3.4.2 to 3.4.5.1 (I upgraded one upgrade at a time in between versions).

BTW, the error messages I am getting when I try to update to 3.4.6 are about forty lines with this type of language:
Warning: main(/home/xxxx0/public_html/ood/wp-content/themes/atahualpa346/functions/bfa_theme_options.php) [function.main]: failed to open stream: No such file or directory in /home/xxxx0/public_html/ood/wp-content/themes/atahualpa346/functions.php on line 65

Any ideas? At least hopefully if someone else is having a similar problem they will respond to this and let y'all know.

UPDATE: Monday March 8th. I'm still having this problem where I have to keep logging in and I'm losing data. It is really frustrating. There have been a lot of people who have read this message, but no responses or indication that anyone else is having the same problem. I wonder if it is a Wordpress problem. This is becoming very discouraging. It is still happening at random. I am about to begin using a different editor than Wordpress. Autosave is not working. I am having to save draft after every sentence in order to not lose data because it is happening randomly. I start thinking okay it's not going to make me sign in and lose data and boom, I lose a whole paragraph. Thanks for any suggestions.

UPDATE: Sunday March 15th. This problem is still occurring for me. It just so happens that I was able to upgrade to a much better desktop computer, and am using Windows 7 now. And it is still happening at random. It had not happened for several days, but now I just lost half of a post that I spent about twenty minutes composing. If I ever figure out why, I'll report back.

Mrs. Accountability
Out of Debt Again