actually this themes is tested on IE until IE 9. we are not supporting IE bellow than IE 8 yet. and actually we are passing compatibility test that have been done by reviewer for IE also before we can advertise this themes is compatible with some browser. i think its can be achieved by adding some plugin.
you can do it by adding this css and put it on additional css on wordpress admin panel > appearance > jkreativ dashboard > additional css :
also for circle loader, its cannot be change unless you change js file.