I have this working ok on 4.1.11 now.
There would be better ways of doing this but try this BACKUP FIRST!!!
In your product.tpl
Change
Code:
{include file="product_thumbnail.tpl" productid=$product.variantid image_x=$phpss_dyn_img_width|default:$product.image_x product=$product.product tmbn_url=$product.tmbn_url id="product_thumbnail" type="W"}
To This
Code:
{include file="product_thumbnail.tpl" productid=$product.variantid image_x=$phpss_dyn_img_width|default:$product.image_x product=$product.product tmbn_url=$product.image_url id="product_thumbnail" type=$product.image_type}
Then Change
Code:
{include file="product_thumbnail.tpl" productid=$product.productid image_x=$phpss_dyn_img_width|default:$product.image_x product=$product.product tmbn_url=$product.tmbn_url id="product_thumbnail" type="P"}
To This
Code:
{include file="product_thumbnail.tpl" productid=$product.productid image_x=$phpss_dyn_img_width|default:$product.image_x product=$product.product tmbn_url=$product.image_url id="product_thumbnail" type=$product.image_type}
This is working on a Local install OK.