Wall posts for a standard user are not deletable

Our wall posts for a standard user are not deletable on EVOwall. I've contacted the developer but I cannot replicate this on their demo site. Our site is a fresh install but draws on the database from our previous site (25,000 members approximately, so I don't want to lose it). All membership levels are set to allow all EVOwall actions and also Boonex comment/photo/video adding and deletion. Can you think of anything I may have missed? Admin is able to delete posts, so it's not a javascript/other error. Only standard members cannot delete items they have added themselves.