[totaltec]

Try this in customer/main/product_details.tpl:

  {if $active_modules.Advanced_Customer_Reviews and $product.general_rating.rating gt 0}
     {include file="modules/Advanced_Customer_Reviews/acr_product_details.tpl" break_line="Y"}
  {else}
    {include file="main/visiblebox_link.tpl" mark="1" title="Be the first to Rate This Product"}
      <div style="display: none;" id="box1">
        {include file="modules/Advanced_Customer_Reviews/acr_product_details.tpl" break_line="Y"}
      </div>
  {/if}

Or you could dive deeper into modules/Advanced_Customer_Reviews/acr_product_details.tpl and use the same logic {if $product.general_rating.rating gt 0} to hide just the stars and be left with just the link or nothing.

I think the point of displaying the stars is to draw attention and inspire reviews, but this should have the same effect.