Justhost addon domain 404 Error

Ok, so I may have to get a web developer on this one because Justhost.com can’t help me oout for some reason.

I’m having a problem with the htaccess file on my hosting account. It gives me a 404 error when I browse to my addon domain, which is theconceptoffit.com, but when I remove it my primary domain (www.chiomaozuzu.com) says, “too many redirects” and the browser doesn’t work.
Here is the code from the file:
RewriteEngine on
RewriteCond %{HTTP_HOST} ^chiomaozuzu\.com$ [OR]
RewriteCond %{HTTP_HOST} ^www\.chiomaozuzu\.com$
RewriteRule ^index\.php$ “http\:\/\/www\.chiomaozuzu\.com\/” [R=301,L]

RewriteOptions inherit
# Use PHP5 Single php.ini as default
AddHandler application/x-httpd-php5s .php
RewriteCond %{HTTP_HOST} ^.*$
RewriteRule ^www\.chiomaozuzu\.com\/index\.php\/?(.*)$ “http\:\/\/www\.chiomaozuzu\.com\/$1” [R=301,L]

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ $1.php [NC,L]

ErrorDocument 404 /404.html

I did all I could, but everything myself or someone tampers with the htaccess, one of my sites wont work. I just want the both to work. What should I do? Thanks so much for reading.