LMS (EKP) shows blank screen in Internet Explorer 11 (AS2)

Hello fellow e-learning members,
 

At the moment I am testing a project that needs to run in a LMS (Netdimensions). A specific wish of the company involved is to run the course completely (and only) in HTML5. For practical reasons they do not want to use flash.

To force the use of HTML 5 I have made a change in the index_lms.html file. If this is relevant for what comes next, I don’t know, but I want to be as complete as I can. The method I used was suggested by another member. For who wants to know more about it, check out the following link.
 

https://community.articulate.com/discussions/articulate-storyline/force-html5-even-with-flash
 

When testing the course in Google Chrome, it works fine. If I try to do the same in Internet explorer 11, the course tries to open in new window, but the window stays blank. I have not configured the player of storyline to launch in a new window, in case that may be a question.
 

What makes it even stranger, is the fact that I have tested the same course (SCORM 1.2) in another LMS and there it works perfectly fine in both Google Chrome and IE 11.
 

I hope someone has encountered the same problem as I did and found a way to deal with it? Anyone who can shed light on this matter, is most welcome to come up with suggestions.
 

Thanks in advance for your comment.