Also purchased not showing

Bit stuck on this, I can't get Also Purchased to show on the product page, I've looked on the forum and I think I've turned it on in all the right places but its still not showing.

what confusing is, if I alter the code in "tpl_modules_also_purchased_products.php"
changing the first line $zc_show_also_purchased = false; to true, makes the header show but not the products.
So to me it looks like it could be one of the admin switches, but I can't figure out which one.

This is probably something simple, but I'm stuck please help!

If I were you I would leave also purchased off it clutters the page and distracts the customer from what they want. best to spend you time on atrributes that are relevant to the products they are buying ie a battery toy has a radio button below to add battering and another below that to add the charger. this works and willincrease the average sale by about 4%