This is to get the manufacturer on your products_t.tpl tempate
{if $products[product].manufacturerid ne 0}
<br />
<div align="center">
<img src="image.php?id={$products[product].manufacturerid}&type=M">
</a></div>
{/if}
<br />
Just above {<a href="product.php?productid}
Not sure about the other 2 sorry.
Greg