Taxes and shipping problems

I’m having a problem with the e-commerce plugin not calculating the tax properly. I have it configured that if you are in Canada and British Columbia, it charges 12%. The second variable is that All Markets are set to 5%. When I originally set this up a few months ago it worked, but now it only charges 5% tax on all orders.
I also have shipping set up based on a Table Rate. It works, but doesn’t add the shipping unless the customer selects it. My problem is that I don’t think the customers will click on the shipping. They get charged $0.00 if they don’t, so why should they?
Can anyone help me with this?
The site is the shop portion of http://www.scentimentalcreations.com.

https://wordpress.org/plugins/wp-e-commerce/