Apache rewriteRules act differently on different hosts/shared hosts. A Zend Framework installation

I was testing the Zend Framework on a shared host and it happens that they do not allow modication of your Apache virtual host Document Root. Meaning if you are using a Zend Framework or some other CMS that requires you to point to a directory within your document root say a sub directory named /Public you may have some problems.

To solve this problem this .htaccess worked on my shared host:
credits too: http://www.alberton.info/zend_framework_mod_rewrite_shared_hosting.html

RewriteEngine On
RewriteRule ^\.htaccess$ - [F]

RewriteCond %{REQUEST_URI} =""

RewriteRule ^.*$ public/index.php [NC,L]

RewriteCond %{REQUEST_FILENAME} -f

RewriteRule ^.*$ - [NC,L]
RewriteCond %{REQUEST_URI} !^/public/.*$

RewriteRule ^(.*)$ public/$1 [NC,L]
RewriteRule ^public/.*$ public/index.php [NC,L]

The above .htaccess worked fine in my Shared host but DO NOT work in my own dev box running Ubuntu with PHP as an Apache module. I keep getting "Request exceeded the limit of 10 internal redirects due to probable configuration error." problems in Apache.

To rectify this i have to edit the .htaccess again to:

RewriteEngine On

RewriteRule ^\.htaccess$ - [F]

RewriteCond %{REQUEST_URI} =""

RewriteRule ^.*$ public/index.php [NC,L]

RewriteCond %{REQUEST_URI} !^/public/.*$

RewriteRule ^(.*)$ public/$1

RewriteCond %{REQUEST_FILENAME} -f

RewriteRule ^.*$ - [NC,L]

RewriteRule ^public/.*$ public/index.php [NC,L]
I also  have to "retain" the original .htaccess that comes from ZF in the Public directory where as in my shared host i have to REMOVE it or I will keep getting Error 500.

To conclude, I have no idea why different rewrites work from the other. I dont know if its Apache version, PHP version, compilation whatevert. I am pretty much clueless actually but try to mix match i guess if things doesnt make sense?