imgs & layers

I am currently trying to build course content with h5p course presentation.
I have two major problems:
- I need to include images to the pop-up box for text "displayed as button". I have a key text and would like to add detailed information in this info box. I set a mark in "displayed as button" However, if I copy paste an image to the text box, it is visible in the edit mode, I can add sizing altenate text etc, but after saving, it's gone.
- when I build layers, and try to make a change in the bottom layer (lets say the background image), the layers (textboxes) above are not visible anymore.
Any idea and help on this?
Would there be a way to integrate the CKEditor?
Both problems are serious for me, because if I have to modify any content in a layer and other layers above are invisible after, then it means I always need to start from scratch and that would be a no-go for using it. Thank you.

I really cannot figure out how I could change the code so I would be able to add images via a button.
I am currently creating an elearning module and have many screenshots which I would like to "hide" through buttons.
If I only would know how to chg the code...

Check out example code here for allowing img tag:

(replace h4 with img)

 - H5P already uses ckeditor

 - Coursepresentation doesn't support layers yet. You'll have to change the code, change the order by changing the order you edit the items in or change the order or add z-index to the html content stored in the database table h5p_nodes