I had the same problem of having it working on the blog list but not in a page displaying only one category of posts (not the /category/category-name, one that I created with a <?php query_posts( ‘cat=4’ ); ?> query). But this latest function fixed the problem:
function my_load_infinite_scroll( $load_infinite_scroll ) {
if( is_page('my-page-name') )
return true;
return $load_infinite_scroll;
}
add_filter('infinite_scroll_load_override', 'my_load_infinite_scroll');