Created attachment 94618 [details] example presentation showing bug Look at slide sorter for attached presentation...
Also, pictures are upside-down in "slides" selector window.
I can not reproduce with Version: 4.2.1.1 Build ID: d7dbbd7842e6a58b0f521599204e827654e1fb8b Ubuntu 13.10. Closing as works for me, please reopen if it's still happen for you in the latest unstable version. Sophie