Hi,
1/ My bad for the download of the images ; I read the import class too fast.
2/ HikaShop is not design to work with external images mostly because it generate thumbnails.
It could be possible to modify HikaShop in order to store some image URL and display them in the product pages ; but at this moment you will have some issues with the product listing and you should deactivate the thumbnail system.
You will also have issues with images in the emails, in the cart, during the checkout, etc.
So, that's something which could be possible but which I can't recommend like that due to the side effects.
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.