[Plugin: NextGEN Gallery] Nggallery hack – simple PHP question for the experts!

I am using a theme called Portfolium. I want to display an NGgallery slideshow in a portfolio page

I have got as far as calling a Custom field (NGgallery id) but don’t know the syntax to parse the result correctly in single-portfolio.php which is the PHP that renders the portfolio page

Simple stuff for you PHP experts:

1 – do the [slideshow= bit – <?php include do_shortcode('[slideshow id='); ?>
2 – pull out the gallery id – <?php $key="--nggalleryid"; echo get_post_meta($post->ID, $key, true); ?>
3 – put the end on the slideshow tag – <?php include ' w=785 h=521]'; ?>

I don’t know if include is the right code and I can’t get the string to parse properly & work. It’s a syntax thing

the last thing I tried was this:

<?php include do_shortcode('[slideshow id=' $key="--nggalleryid"); echo get_post_meta($post->ID, $key, true); echo ' w=785 h=521]'; ?>

I used this as the custom field name: –nggalleryid

Help!