There is a problem with the_content filter running in an infinite loop, you can check this by opening a file wpadverts/includes/shortcodes.php (going to the line about 407) and replacing line
$post_content = apply_filters("the_content", get_post( $post_id )->post_content );
with
$post_content = apply_filters("adverts_the_content", get_post( $post_id )->post_content );
There is a problem with the_content filter running in an infinite loop, you can check this by opening a file wpadverts/includes/shortcodes.php (going to the line about 407) and replacing line $post_content = apply_filters("the_content", get_post( $post_id )->post_content ); with $post_content = apply_filters("adverts_the_content", get_post( $post_id )->post_content );