I had exact same problem as Pedro. Wracked my brain to get the post to display and wondered what was wrong. Pedro’s solution to remove that line from the advanced-post-slider.php file worked great! Thanks! Hopefully this will be fixed in a future update of the plugin. It always exclude the most recent post from the slider, which it shouldn’t do. If the post is not the most recent post of all the posts, it’s fine. Whew!
And Digontoahsan is wrong. It is not only the current page or post where you have the slider. I am showing this slider on a custom home page and use the same PHP code as Pedro for that page, so there is definitely a bug of the plugin excluding the latest post from the slider if the slider is used on the blog home page.