This is less of an IH2 "issues" and more of a function of how additional images in general work in Zen Cart which IH2 works WITH but does not alter.
More information on how additional images work in Zen Cart can be found here:
How do I add multiple images to a product?
https://www.zen-cart.com/tutorials/index.php?article=58
This is only partially true.. Using these image names as an example, this will be the result.
Product 1 has main image named giftbx.jpg
Product 2 has main image named giftbx1.jpg
Product 1 will display giftbx1.jpg as it's additional image
Product 2 will display giftbx.jpg as it's additional image
Adding IH2 to this mix, let's say you upload 3 additional images to Product 1. Regardless of the source file name, IH2 will rename those images based on the main product image. So an image named necklace.jpg, necklace1.jpg, necklace2.jpg uploaded to Product 1 via IH2 will be renamed as follows:
giftbx_01.jpg
giftbx_02.jpg
giftbx_03.jpg
After you upload the additional images this will be the result:
Product 1 will display the follow additional images:
giftbx1.jpg
giftbx_01.jpg
giftbx_02.jpg
giftbx_03.jpg
Product 2 will display the follow additional images:
giftbx.jpg
giftbx_01.jpg
giftbx_02.jpg
giftbx_03.jpg
More on how additional images in Zen Cart works can be found here:
Why am I seeing images for other products on my product pages?
https://www.zen-cart.com/tutorials/i...hp?article=315
If you want products to share additional images and use the IH2 controls for uploading those additional images, it can be done, but you will REALLY need to plan out the naming of your main product images.