Hello,
My advice would be to not activate the "please select" setting for the state custom field.
There was a patch some weeks ago regarding an issue that customer can't register for some countries without states (since the state was required).
I got the impression that the current patch is not what it should or you do not have the latest version of the patch.
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.