Reverting back to an old skin/theme - need help

Hi everyone,

I was using one of Jalokim's hitskins and since the problem on his Photobucket account, I'm using a temp theme/skin. I have some questions sorry. I have always had problems switching back and forth between skins so I need to be sure on how to do this.

One strange thing, when I go into my admin panel and "Skins management", my old theme isn't showing at all anymore. Even if I pull up a date before I switched to this temp theme. When I first switched themes, the old one was showing for prior dates.

Why is this?

How do I switch back to my old theme/skin when the time comes? I copied my entire CSS code from the old theme so could I simply clear the CSS I have in there now and copy the old CSS back and click save?

I am just so afraid of messing up my old theme because it had been customized a lot from the original them with different colours of text, other modifications as well.

Help!