Hi,
If your modified your views thanks to the view override in HikaShop (backend > HikaShop > display > views) and the CSS in the HikaShop configuration panel, these overrides will be stored in folders that won't be replace/removed with updates.
So it allows you to update/upgrade without any kind of problem.
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.