Okay. I downloaded and installed Rainlendar 2.0 (http://www.rainlendar.net/cms/index.php) (the Lite version) just weeks ago, and I need to download and install skins. I know where to download skins. I have a question: How can I install skins for Rainlendar 2.0?

Go to My Computer >> C: >> Program Files >> Rainlendar >> Skins >> And put the skin there. (it must be in a map) :)

Okay. The skin file have the extension .r2skin for Rainlendar 2.0. Should I drag and drop new skins with the .r2skin extension from the download folder to the Rainlendar2 skins folder? (C:\Program Files\Rainlendar2\skins)

Yes.

Okay. I can't find what I want, so I'll create my own. What tools/programs should I need to create a Rainlendar skin?

There are no programs, exactly. It's coding you need to know.

How can I create new skins?
Written by Kimmo Pekkola
The skin documentation and tutorials are not ready yet so probably the easiest way is to take the Shadow4 skin that comes with Rainlendar and start modifying that.
Rainlendar2 skins (.r2skin) are just normal zip archives with different file extensions. The archive contains few xml files and the resources (images, scripts, ...). The skin.xml file must be in the root of the archive so make sure that when you are zipping the archive after modifications that it doesn't contain any extra folders.
During skin development you can also just unzip the archive into Rainlendar's skins-folder. This way you don't have to zip it again after each change.