Newb needs help with shipping

Hello,

I am trying to get the shipping configured. Since OpenCart does not have a module pre-installed to charge shipping based on the amount of the sale, I thought I would just have PayPal or Google Checkout do the calculating. However, checkout stalls at shipping details with the following message:
How can I get it to move on to the next stage, or would it be better to have OpenCart calculate the shipping? I am running OpenCart Version 1.5.3.1 on an Apache server. I will consider installing a module into OpenCart if it is not too difficult. Below is how we would like to charge for shipping:
Here is the site: http://www.justetchinit.com/shop/

Thanks for your help!

You are better off having Open Cart do the shipping.
There are many extensions that do this. Here is one:
http://www.getclearthinking.com/shippin ... d-shipping

You would be good to buy that, he's one of the better devs.

Thanks, we will seriously consider buying that module. For right now, I turned on Flat Rate shipping and set it to zero in the cart. Google Checkout and PayPal then calculate the shipping. I appreciate the help!!!