@carolacat: the slider uses jquery to display posts, so if you have other plugins that use jquery, it may cause problems with the slider. Try disabling those other plugins.
@TomStock1337: this is mostly likely related to a recent 1.5.5 update. A bug report has been filed in the Graphene support forum; you can follow its progress here: http://forum.khairul-syahir.com/bug-report/post-excerpts-and-some-widgets-get-repeated-with-155-update
