Change medium image size results in bad arrows shown

[FaTedev]

As default there are up to 3 images shown below the primary one on a product page which allows the user to view others by clicking or hovering mouse over, pretty standard nice feature. Default set-up is 80*80 pixel images with 3 in a row, when there are more than 3 images then arrows show to scroll the image line left / right.

 

Consider you can change medium image size in back office to 150*150 pixels, now only 2 images fit in the same area but the arrows will still only trigger on 3 images +. I thought this was as simple as changing in Product.tpl area arrows output DIV/SPAN area:

 

{if count($images) > 3} to say {if count($images) > 2}

 

But nothing is working to make it show navigation arrows on 2+ images, I figure this must be because of the standard Prestashop 3 in a row set-up? Am I missing some silly option somewhere or is this hard-coded in a place I've not yet found?

 

Anyone please.