Ok, here's the down and dirty way of doing this if you want to print out fancy invoices. I am not guaranteeing any of the code, nor would I attempt any of this before backing up all the files - before they change - in case you have to fall back. With that said, here we go:
1) Find the file include/history_order.php
2) Find the following line of code:
Code:
if ($mode == "invoice" or $mode == "label") {
3) Change
Code:
if ($mode == "invoice" or $mode == "label") {
to
Code:
if (or $mode == "label") {
4) Find the file skin1/main/order_invoice_print.tpl
5) Find the following line of code:
Code:
{ include file="mail/order_invoice.tpl" order=$orders_data[oi].order customer=$orders_data[oi].customer products=$orders_data[oi].products giftcerts=$orders_data[oi].giftcerts}
change it to
Code:
{ include file="mail/custom_order_invoice.tpl" order=$orders_data[oi].order customer=$orders_data[oi].customer products=$orders_data[oi].products giftcerts=$orders_data[oi].giftcerts}
6) Using the variables from your order_invoice.tpl file make a file called custom_order_invoice.tpl - here is where you are going to use HTML to make it look fancy. Save it to your mail directory.
There is one more include in the order_invoice.tpl file "{include file="mail/order_data.tpl"}" so you may want to change that line and make your own customized tpl for that too.
I hope this is clear, and that it helps stop all the name calling.