Hello @fcsab
Sorry about the inconvenience. I couldn’t reproduce the issue you are facing. We might need to take a look at your site. So, it would be better if you send a mail regarding this issue and for the faster support. This is the email address support at themeum dot com.
Thank you
@fcsab @probillals There has been a similar issue described on the H5P forum (H5P content not rendering if the lesson list navigation is used) where I have posted an analysis and a one-line hack to fix the problem. Please check https://h5p.org/node/1133837#comment-40838 in case that’s relevant for you.