Centering counterform 2012

I would like to refer to an earlier question.
I've been away for about a week so it expired.

http://support.cargocollective.com/discussion/24278/centering-counterform-2012

Thank you for the earlier answer.
It worked for the thumbs and the pictures but not for the slideshows.
Probably because i didn't insert the html snippet.

Since i don't have an upgraded account, in which i can't use html, is there another way to fix this?

FYI: For the moment I saved my css code with everything David Boni suggested, except the html part.


Thank you in advance.

Jonas