Customizing Marketpress Shipping Options

Hi there,

For the site I am creating I need to be able to add a few different shipping options:
e.g.
$2.60 Standard Post
$4.40 Tracked Post
$7.20 Tracked Post with Rural Delivery

etc.

Also, I would like to have combined shipping per order e.g. customers can choose from the applicable options (like mentioned above) at the checkout, and only pay one shipping cost per order (the site does do not need to charge shipping 'per item').

Is there a way I can implement both of these features?

Cheers...