1.4 or later.
Only the JDK. Simply download the binary distribution and unzip somewhere on your local filesystem.
The binary scripts are in the bin/
directory, which should be added to the system path.
Yes, see download for more details.
The user must specify a sitemap, a skin and an output directory, see getting started for more details.
The sitemap specifies the content of the website, see sitemap for more details.
The skin is the template of the website pages, both in terms of layout and of style, see skin for more details.