Guests see restricted page on random page tabs

My event plugin site, http://wp-events-plugin.com uses the membership plugin. I haven't upgraded for a while due to conflicts with BP in the first versions of this plugin, requiring me to hack, but now I got rid of BP and everything is (almost) running smoothly.

The problem I had was the first two tabs on my home page (using the MyProduct theme from Elegant Themes) had the 'Upgrade for access' page content showing, no matter which page I selected. Strangely it showed the third and fourth tabs fine. (screenshots working/not working attached)

The tabs are loaded using query_posts and looping through them.

Jumping into your plugin, I can see the issue is caused by you membershippublic::ensure_option_pages_visible() function, and my current fix is adding this around the code getting affected:

global $membershippublic;
remove_action('pre_get_posts', array(&$membershippublic, 'ensure_option_pages_visible'), 999 );

query_posts(array....
while (have_posts()) : the_post();
....
endwhile; wp_reset_query();

add_action('pre_get_posts', array(&$membershippublic, 'ensure_option_pages_visible'), 999 );

Any insight on what's causing this would be nice. Thanks!