[TYPO3-shop] Payment handlescript shows BASKET_ORDERCONFIRMATION_TEMPLATE page instead of the desired output

[Juan Pablo Villaverde]

I have a custom Payment Handlescript, but the same behavior is show with
DIBS of an empty handlescript.

The BASKET_ORDERCONFIRMATION_TEMPLATE page is shown instead of the desired
output.

tt_products runs the handlescript because I put debugging in the las line
and everythis is calculated OK.
I put a die($content); and I see the correct prepared content. But I remove
the 'die' and typo just shows the order confirmation subpart instead of the
$content.

And I also have another problem, in the handlescript, I try to read a
template subpart in this way:
  $content=$basketView->getView($tmp='', 'PAYMENT', $address, false, false,
true, '###BASKET_TPV_STARTER###',$markerArray);
and I only get an empty string (for the test in the previous problem I used
$content="test";). I have the subpart ready in the template file. It happens
with any subpart

I tried to figure out the problem but I'm a little lost now, any help will
be very appreciated!

jp