I tested the latest version of LayerSlider (7.0.4) by updating in a development area and I had some trouble when editing a project. It is not possible to switch between the slides, there is always only the first slide shown to edit…
Also if you open project settings it is not possible to close the window. You need to change the url manually to get back to wp-admin…
So I created a support ticket at kreatura support. Here is what the answered:
We find the issue, it is related to a very old version of jQuery (which has been used by WordPress 4.9). We will try to fix this in the next update. In the meantime, you can try to update the jQuery of WordPress to the latest version - it should solve that issue. Or if you need that old version of jQuery, we recommend to use LayerSlider 6, while we fix that.
We are sorry for your inconveniences.