Dear user , As you know we have include LayerSlider Plugin in our theme.
So if you are getting error to active LayerSlider then please don't try again.
Activation code is just for auto updates, LayerSlider will work fine without activating.
When Plugin will update we will include Latest file in our theme package.
For more information you can visit this link.
https://support.kreaturamedia.com/docs/layersliderwp/documentation.html#activation-bundles