date format, name order

Hi,

There is not a single place where you change the date format for all the date display. In the next version of HikaShop it will be easy as you'll be able to to it from a central place, via a translation override, but for now, it would require to edit each view file where you want to change that. Could you be more specific about where you want to change the date format ?

Regarding the Surname/Firstname in the "confirmation", I suppose that you're talking about the Firstname and Lastname address fields which are displayed in the order status notification email which is sent to the customer when the order is confirmed.
In that case, you need to edit the files address_template (one for your frontend template, one for your backend template) via the menu Display>Views and just change the order of the tags in there to have them like you want.