We can't provide support I'm afraid, but you should find it all quite simple.
Download the latest release from the downloads directory.
Untar the file into your web root. You should now have a working demo.
If it doesn't work, you may not be allowing .htaccess to override Apache settings. Check your config for the line "AllowOverride All", or provide a list of overrides if you'd feel safer.
Here's our .htaccess file. Steal bits and make your own;
# Error Pages
ErrorDocument 404 "File not found"
# Templates
HeaderName header.html
ReadmeName footer.html
IndexIgnore header.html footer.html etc
# Functionality
AddHandler server-parsed shtml
Options +Indexes
Options +IncludesNOEXEC
# Listing Settings
IndexOptions +DescriptionWidth=60 +FancyIndexing +ScanHTMLTitles +SuppressHTMLPreamble +TrackModified +XHTML
IndexOptions +NameWidth=50 +SuppressLastModified +SuppressSize
# Custom Descriptions
AddDescription "Please read me first :)" README
AddDescription "You're not supposed to see this file." header.html
# Icons
AddIconByEncoding (CMP,/etc/icons/compressed.png) x-compress x-gzip
AddIconByType (TXT,/etc/icons/text.png) text/*
AddIconByType (IMG,/etc/icons/image.png) image/*
AddIconByType (SND,/etc/icons/sound.png) audio/*
AddIconByType (VID,/etc/icons/movie.png) video/*
#AddIcon /etc/icons/binary.gif .bin .exe
#AddIcon /etc/icons/binhex.gif .hqx
#AddIcon /etc/icons/tar.gif .tar
#AddIcon /etc/icons/world2.gif .wrl .wrl.gz .vrml .vrm .iv
#AddIcon /etc/icons/compressed.gif .Z .z .tgz .gz .zip
#AddIcon /etc/icons/a.gif .ps .ai .eps
#AddIcon /etc/icons/layout.gif .html .shtml .htm .pdf
#AddIcon /etc/icons/text.gif .txt
#AddIcon /etc/icons/c.gif .c
#AddIcon /etc/icons/p.gif .pl .py
#AddIcon /etc/icons/f.gif .for
#AddIcon /etc/icons/dvi.gif .dvi
#AddIcon /etc/icons/uuencoded.gif .uu
#AddIcon /etc/icons/script.gif .conf .sh .shar .csh .ksh .tcl
#AddIcon /etc/icons/tex.gif .tex
#AddIcon /etc/icons/bomb.gif core
AddIcon /etc/icons/back.png ..
AddIcon /etc/icons/readme.png README
AddIcon /etc/icons/folder.png ^^DIRECTORY^^