Hi,
Sorry, I haven't any kind of problem for uploading an image to your product.
First I removed the barcode image and I add a new one. I upload my image and validate it.
The image thumbnail was not working in the first time. I guess that the image generated was not accessible in the same second but if I click on the image, I have the the right preview.
After that I save the product and the image was stored correctly.
I also try the gallery selection, working good too.
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.