Set of images/links as custom values associated to a post.

Hello wp gurus,
Here is a big problem for me and hopefully a small one for you:
I am building a portfolio/blog; all projects-related posts have a set of images associated to them in the form of custom fields like:
key=gallery value=”link to image file”

These images will be displayed in a slideshow (Smoothgallery) so I need my wp template to repeat a code snippet containing a couple of variables, like the link to the img file, the title of the image and its description.

This is the part that needs repeating in the rendered html:
code

<div>
<h3>Image_1_Tile</h3>
<p>Image_1_Description</p>
<a href="BigIMG"></a>
<img src="MediumIMG" />
<img src="ThumbIMG" />
</div>

code
What I need the most is to get the links to the image files; the title and description are less vital in case they make the prolem overly complex.

I checked the Get Custom plugin, but I can’t seem to find a way; also went extensively through the codex and landed on many sites like The Udersigned. I’m lost.

Thanks,

Tommaso