Embeded Image Block - Any way to choose image size ?

I have the following code, which works, on the front page of my site..

<?php
$ch = curl_init();
$timeout = 5; // set to zero for no timeout
curl_setopt ($ch, CURLOPT_URL, 'http://www.ourdarkskies.com/gallery2/main.php?g2_view=imageblock.External&g2_blocks=randomImage&g2_show=title&g2_itemId=214');
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
$file_contents = curl_exec($ch);
curl_close($ch);
echo $file_contents;
?>

This works great, and gets me a random image from a spefic ablum, however it will only return the thumbnail size of 150px, is there away to make it return a larder size? I tried g2_maxSize and g2_minSize, they do not appear to have an effect.