sorry to be such a pain...

I also get this:

Forbidden

You don't have permission to access /www/cms/rewritetest.php on this server.
Apache/2.0.59 (Win32) DAV/2 PHP/5.2.3 Server at localhost Port 80

What do I comment out of the code? Not a PHP wizz like yourself

Test Platform:
Uniform Server 3.5-Apollo
Windows XP Home
silverstripe-v2.1.0

Test results and problem area

1) http://localhost/ss/install.php

MySQL server: localhost {corectely detected}
MySQL username:root {corectely detected}
MySQL password: root {default password manually add this}

Warnings (Hence not a problem these files are writable on Windows XP Home):
Is the .htaccess file writeable?   Unable to detect whether I can write to files. Please ensure W:/www/ss/.htaccess is writable.
Is the mysite/ folder writeable?   Unable to detect whether I can write to files. Please ensure W:/www/ss/mysite is writable.
Is the tutorial/ folder writeable?   Unable to detect whether I can write to files. Please ensure W:/www/ss/tutorial is writable.
Is the assets/ folder writeable?   Unable to detect whether I can write to files. Please ensure W:/www/ss/assets is writable.

Development servers: {corectely detected}
localhost
127.0.0.1

At this stage .htaccess not written to.

2) Click Install: I am nowrunning through ... will take about 30sec

On completion this error message is produced:
Forbidden
You don't have permission to access /ss/rewritetest.php on this server.

Note 1: phpMyAdmin ss_mysite contains 52 tables --- Hence working

Note 2: .htaccess has been written to:

### SILVERSTRIPE START ###
RewriteEngine On
RewriteCond %{REQUEST_URI} !(\.gif)|(\.jpg)|(\.png)|(\.css)|(\.js)|(\.php)$
RewriteCond %{REQUEST_URI} ^(.*)$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule .* sapphire/main.php?url=%1&%{QUERY_STRING} [L]
### SILVERSTRIPE END ###

This file is incomplete it should look like this:

### SILVERSTRIPE START ###
RewriteEngine On
RewriteCond %{REQUEST_URI} !(\.gif)|(\.jpg)|(\.png)|(\.css)|(\.js)|(\.php)$
RewriteCond %{REQUEST_URI} ^(.*)$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule .* sapphire/main.php?url=%1&%{QUERY_STRING} [L]
### SILVERSTRIPE END ###
Options FollowSymLinks

Without Options FollowSymLinks Apache gives up. Log file:
Options FollowSymLinks or SymLinksIfOwnerMatch is off which implies that RewriteRule directive is forbidden:

3) Well thats the problem added the line and refreshed the page:

A quick message displayed stating mod_rewrite is working followed by Installation Successful.

Clicked the Delete Install files link --- OK

You can start editing your site's content by opening the CMS.
Email: admin
Password: password

Login --- No problems

Hope that helps

All the best
Ric

Karlim, please post your webserver software. Is it apache? It seems like you might want to contact your hosting company to ask about their support of our software.