Hi,
You're using a Javascript lib to display the radio buttons with another design ; this library does not work properly with the structure and the radio does not receive the "checked" status.
Due to that non modification, the javascript of the radio is not called so the switcher is not switching.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.