BLAST!
Foiled again by WordPress. Aka Problem solved.
All I had to do was create a new file (blog.php) in my content folder with the following information in it:
<?php define(‘WP_USE_THEMES’, false);
require(‘blog/wp-blog-header.php’); ?>
And then use index.php?x=blog.
Sigh. Why didn’t anyone tell me it was that easy in all the other 50,000 posts I read?