Cloning the freeshipper module

I have a client that wants to have certain products with free shipping in the US only and add a handling charge for international shipments. I attempted to clone the freeshipper module and discovered that it's not like the other shipping modules. I was able to get it to work by modifying the zen_get_shipping_enabled function in functions_general.php in addition to modifying the language and modules files. This unfortunately caused problems on the admin side giving me the following error:

[21-May-2012 18:13:10] PHP Fatal error: Call to a member function in_cart_check() on a non-object in E:\wamp\www\shipping\includes\modules\shipping\freeshipper.php on line 25

[21-May-2012 18:13:10] PHP Stack trace:

[21-May-2012 18:13:10] PHP 1. {main}() E:\wamp\www\shipping\admin1\modules.php:0

[21-May-2012 18:13:10] PHP 2. freeshipper->freeshipper() E:\wamp\www\shipping\admin1\modules.php:191

I fear I'm headed down a real rat hole and wonder if someone could point me int the right direction. This if a fresh install on my local machine with the demo products loaded. No mods at all.

DOH! :blush: I fixed it. It helps when you remove the module and then install it again.