Ive noticed that. But error apperas when I choose single article, cat with articles, category made with joomla manager then copy it to k2. Everything new cause problem. I cant use template ;(
It might be the problem with time settings on the server. Please check the time offset settings on the module itself - it might be the case (with time/dates wrong the article is published, but module sees it as future article and treats data source as empty)