So, I hacked the file to make this possible. When I say hack...I mean like a dull machete...it aint pretty, but it gets the job done.
on line 473 of dtbilling.html.php you\'ll find this:
<tr>
<td>
<?php
echo DT_PAYMENT_TYPE;
?>
</td>
<td>
<input type=\"radio\" name=\"payment_type\" value=\"0\" checked> <?php echo DT_PAY_FULL;?>
<input type=\"radio\" name=\"payment_type\" value=\"1\"> <?php echo DT_PAY_PARTIAL;?>
<input type=\"text\" name=\"paid_amount\" size=\"5\" />
</td>
</tr>
I changed it to this:
<tr>
<td>
<!--< ?php
echo DT_PAYMENT_TYPE;
?>-->
</td>
<td>
<input type=\"hidden\" name=\"payment_type\" value=\"1\"> <!--< ?php echo DT_PAY_FULL;?>
<input type=\"radio\" name=\"payment_type\" value=\"1\"> < ?php echo DT_PAY_PARTIAL;?> -->
<input type=\"hidden\" name=\"paid_amount\" size=\"5\" value=\"<?= numberFormat($totalAmount-$rowInvoice->paid_amount,2)?>\" />
</td>
</tr>
And on line 519 or so, you\'ll find:
var form=document.adminForm;
if(form.payment_type[0].checked==true)
Replace it with this:
var form=document.adminForm;
if(form.payment_type == 1)
//if(form.payment_type[0].checked==true)
None of this looks right...not sure why...so read it good.
Hope it helps!