Featured Images not importing - min_width + min_height constants ignored

This is a recurrence of a similar problem from before - some images are not being imported - here is the low down:

The RSS URL:

http://www.greenheartshop.org/blog/feed/

Original posts with a featured image, but no other content images are not re-imported with a featured image:

Original:
http://greenhearttravel.org/global-greenheart-initiative/greenheart-clubgrant/3-reasons-to-join-the-greenheart-club

Auto-blogged result has no image ( all posts link back out to the original, so no way to send a URL to view ).

If I edit the original and add a small 150x150 in the content space - this is pulled in and set as the featured image - but I have the following in the wp-config.php:

// autoblog settings ##
define( 'AUTOBLOG_FEATURED_IMAGE_MIN_WIDTH', 292);
define( 'AUTOBLOG_FEATURED_IMAGE_MIN_HEIGHT', 181);

So, this small image should not be included.

I only have the "Featured Image" add-on active of the two image options.

In the feed settings I have the following option checked:

- Find the first image withing ( within? ) content of a feed item

This site is live and uses a custom theme and a number of plugins - there is, as with most of these cases - no chance to swap to 2012 and turn the other plugins off.

Any extra info required - please ask.