I downloaded and installed AsteriskNOW Version 1.4.0 Beta 1.  As explained, the software and the website is still in beta.  The first sign of beta I saw was that there were no MD5SUM or  SHA1SUM values for the download.  I calculated the sums from my download as such:

md5sum asterisk-1.4.0-x86-disc1.iso && sha1sum asterisk-1.4.0-x86-disc1.iso
291853c2be640a2f1462c37cfac18507  asterisk-1.4.0-x86-disc1.iso
e29ccbd1ed7cecd40150953d38ab0ede96eaa396  asterisk-1.4.0-x86-disc1.iso

Once you have successfully downloaded the ISO file, you must create a disk from it.  Using Fedora Core 6 Linux, you can simply right click and select Write to disc.  If you are using Windows, it may be a little more difficult.  You will need to burn a disk from the ISO.  Note that this is not the same as simply writing the file to disk.  If you do not have the proper software, I recommend the excellent and free CD Burner Pro XP.  Thanks to the Ultimate Boot CD for Windows http://www.ubcd4win.com/index.htm for pointing me to this tool.

Once you have burned the disk you can use it to boot your machine.  I recommend choosing the option to remove all partitions.  Note that this will repartition and format your hard drive, removing all data.  You have been warned.  Another problem I ran into was with the admin password. 

If you have installed other RedHat based Linux distrobutions, you are familiar with entering the root password during install.  Note that AsteriskNOW configures the password for the admin user, not root.  This password will be used for the web-based Asterisk Configuration Engine.  I guess that there is a limitation in the http authentication that prevents you from using special characters, so I recommend using an alphanumeric password.  If you have already installed AsteriskNOW with a more complex password, never fear.  The following steps will help you reset your admin password:

1. From the AsteriskNOW console menu, choose the second option "console"
   
2. Press Alt-F9 to get the the Console
3. Type "!", that's an exclamation point without the quotes, also known as BANG (You are now root)
   
4. Edit /etc/asterisk/manager.conf and replace the secret in the [admin] section.  You can use vi or nano to edit.  nano is more intuitive if you are not familiar with vi.
5. Type "exit" to get back to the console.
6. Hit Alt-F1 then Enter to get back to the AsteriskNOW console menu. 
   

You should now be able to log on to the web-based Asterisk Configuration Engine.