I see that LayerSlider can be auto-installed with X-Theme. The Plugin requires an authorisation code. I tried using the same code as my X-Theme code, but this was invalid. Do I need to purchase LayerSlider as a stand alone plugin to use it – or can I use it at no additional cost when purchasing X-Theme?
There should be no further purchases if you already installed x theme. Try removing the layerslider then reinstall it again using the x theme addson. You will be able to install the compatible layerslider. Probably you installed a different version.