To change the slider settings go to the wp-admin> appearance> theme-settings> slider. http://screencast.com/t/fuIe2q1ZXZbb
You can set the seconds the slider stays on each slider, and choose fade if you just want one image to follow on from the other without the slicing effect.
For any css changes, you can use a web inspector like Chrome Dev tools or Firebug to locate and change the css in real time, then you can just copy/paste the code back into your css file and save. Please see a video example here, make sure you always include the closing brackets or the code won’t work :