Bugs in content types

In course presentation I've added a bunch of png files. These all displayed and my slide show was looking great with 16 slides in total. I designed this all in Firefox. I went to sleep, then in the morning I came to look at it, and now some of the pictures are just blank when I play the presentation. 

Image is not showing on my end this is the error I am having in the console http://prntscr.com/6zrr2g

using Wordpres 4.2.1 nginx php-fpm

Hi 

I have noticed a problem with interactive videos in the course presentation module. When you load the presentation the video controls will not appear. Nothing happens unless you click the more information icon, then the video will immediately play. This does not appear to happen immediately but after it has been saved for a day.

I am using Drupal Opigno.

Regards