There is (basic) support for playback of KML tours in the Tour panel. There's also a patch at https://git.reviewboard.kde.org/r/114531/ which introduces a progress slider for seeking during playback of tours. The patch is likely correct, but does not apply to master anymore. This task is about fixing the conflicts and testing the implementation of the patch. Make sure to test it with tours that play some sounds and verify everything works as expected. Afterwards file a new review request at http://git.reviewboard.kde.org using the marble group as reviewers.
I want to work on this task.