Ubercart

hallo,
I'm modifying the tablerate module because I've seen that it doesn't work (IMHO this is a very useful module but it seems that it is abandoned).
here is the link to this module: http://www.ubercart.org/files/uc_tablerate_0.tar

but now I don't understand why the quote method doesn't print to the screen if I visit the page:
mysite.com/?q=cart/checkout/shipping/quote
so, when I'm in the checkout page when I click on "click to calculate shipping" the system doesn't print anything on the screen.

I've enabled the method under mysite.com/?q=admin/store/settings/quotes/methods

I've attached the file (I've commented some code to do some tests).

any idea is appreciated.

thanks
nicola