Hello There,
Thanks for writing in!
1.) To make the slider as fullscreen, please make sure that you set in the settings as a fullscreen slider. For more information, please check this out: https://support.kreaturamedia.com/docs/layersliderwp/documentation.html#slider-builder
2.) The navigation arrows has it’s own default settings. There are a few skins that you may use. Setting SVG files could mean customizations which is beyond our scope of support.
3.) It also worth mentioning that in responsive mode LayerSlider only scales the layer element itself to gain extra performance. The content inside should adapt the dimension changes on its own. While this happens automatically in most cases, shortcodes and complex HTML might not be resized in sync with the slider.
For more added information, you can the documentation here: https://support.kreaturamedia.com/docs/layersliderwp/documentation.html#introduction
Hope this helps.