Sorry to be a pain. I use post tiles on our highlights page here > http://www.basic.fm/?page_id=39 and I can set the number of tiles displayed to any amount I want.
I wanted to use post tiles on and archived page also http://www.basic.fm/?page_id=2555 but no matter what I do it is sticking to the default 8 tiles.
The shortcode I am using is [post-tiles categories='174' posts='82']
Is there a conflict between the 2 pages?