Style and edit CENTRE COLUMN not working

Wordpress 2.8.4
Atahualpa 3.4.2

I have just updated the theme and discovered some unusual problems.
for permalinks I had index.php/%post_id% which worked well in the previous version now it always goes back to homepage.
Default permalink works.

I select 'style and edit CENTRE COLUMN'
Whether I make a change or not I get "website is unable to display webpage" HTTP 501/HTTP 505.
I cannot make any changes to the stylesheet.

Other style pages work ok.