different rates charged for adult/child on booking

Hi,
I just purchased event bookings extensions and not sure if it can do what I'm after-hopefully it can.

I wish to setup an event where people can book a time slot to meet santa and they have to enter the number of kids and adults in booking and will be charged on these details. The adults are cheaper than the kids bookings.

Is this possible?

Found this link
joomdonation.com/index.php?option=com_ku...iew&catid=65&id=8616
which helps

but there is still an issue,

once booking is completed it doesn't go to paypal.
I guess because the cost in the original event is €0, it won't direct me to paypal but I added in users cost via the custom field and the cost is >0, but it doesn't send me to the paypal site

e.g.
original cost+ custom field adult1 and customer field child1

0 + 5 +10= total 15$


Any tips would be greatly appreciated.
Thanks in advance