You can build a point and click interface, but also drag and drop or just point. The examples on this site support this claim. Most of the documentation is in HTML format. It is best read using a Java enabled browser. There is no automated installation procedure, because there is hardly anything to do.
Installation just involves untarring or unzipping that same file in the right directory.
Tar is mainly Unix oriented. Zip files can be read on almost any platform, as long as you have the right tools. We have unzip for Unix. MS-Windows 95 users must make sure their zip utility can extract files and directories with extended names. The documentation explains the structure of script files.