Hi Mobilepro,
On our Window servers PHP is located at C:\PHP5\php.exe, so when you use BASE_PATH you're actually getting C:\PHP5. A quick fix that I can recommend is replacing your relative paths with the fully qualified path to your files.
For example, take this code
<?php
define('BASE_PATH','./');
include BASE_PATH . 'manage/functions.php';
?>
and replace it with something like this
<?php
define('C:/HostingSpaces/user/domain.com/wwwroot/path/to/application');
include('C:/HostingSpaces/user/domain.com/wwwroot/path/to/application/manage/functions.php');
?>
Hope this helps, let us know if you need anything else.