Post duplicate. Script problem?

[cje]

I probably got a script problem.

When I added the "featured content gallery" plugin and selected a category to be displayed the content of the gallery was displayed successfully in the "slideshow". But the content of the posts was also displayed beneath the slideshow (as a normal posts, but before my other posts) ....?
So, the extra post was displayed between the slideshow and the correct posts bellow.

I've been tweaking and reading w/o finding a good solution. I've also tested the "Advanced Category Excluder" w/o any success.

Thanks for any suggestions