Just switched from Marketpress Pro 18.104.22.168 and WP 3.9.1
Selected UPS for the shipping calculator, with Hong Kong as the base country, and regardless which variables I choose for the UPS calculator i always get the error
"This measurement system is not valid for the selected country."
Changed the base country to Canada, and it works beautifully!
here's a previous thread with the same issues unsolved.