Paypal IPN + Coldfusion 7 not working?

I am trying to set up coldfusion to handle payPal IPN but I cant find any tutorials that explain how to get it to work, anything I find is out of date or I just cant get it to work.

I've tried using the code on paypal developer site here:

https://cms.paypal.com/cms_content/CA/en_US/files/developer/IPN_COLDFUSION.txt

and I have enabled IPN on my paypal account but I'm not sure I've set it up correctly. Is there a way to check if paypal is even sending data back to my site?

Been having a look and it seems the ipn I set up isnt even running. when I test the payment (i set up a basic ipn.cfm file that writes to a text file) it still doesnt work. Could there be a reason why paypal isnt running the ipn? If I go to the ipn.cfm file in a browser then the test txt file is created.

Cheers!