slideshow loads pictures after 20sec

using wp 2.8.3 and ngg 1.3.5
ON my sidebar I have a different slideshow for each page using custom fields, my problems is that the slideshow load pretty quickly – at the least the loading icon does, but the pictures only turn up after half a minute. What can be done to fix this? the pictures only weight 20kb in average.
the page in question is https:// topsolar dot co dot il/how-it-works/

I would really appreciate any advice on that

Thanks – Omer