Okay ... I goobered up on that one ... it worked for something else I wrote for a client ... 
Now for the real way to make Downloads track ...
Customize the order class file:
/includes/classes/order.php
Find the lines:
Code:
// do not decrement quantities if products_attributes_filename exists
if ((DOWNLOAD_ENABLED != 'true') || $stock_values->fields['product_is_always_free_shipping'] == 2 || (!$stock_values->fields['products_attributes_filename']) ) {
Change to read:
Code:
// do not decrement quantities if products_attributes_filename exists
if (true || (DOWNLOAD_ENABLED != 'true') || $stock_values->fields['product_is_always_free_shipping'] == 2 || (!$stock_values->fields['products_attributes_filename']) ) {
NOTE: Downloads are NEVER Virtual Products ... Downloads are NEVER Always Free Shipping ... Downloads "know" that they do not need shipping ...