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Or specify the images via Magento Attribute.
Only Text, Multiple Select or Dropdown type attributes can be used and must contain absolute urls. 
In the text type attribute urls must be separated with a comma.
e.g. http://mymagentostore.com/images/baseimage1.jpg, http://mymagentostore.com/images/baseimage2.jpg
Change Images for Attribute
- Change Images for Attributes (applied only to Configurable Products) – allows selecting Magento attribute by which the Multi-Variational Product images will be switching on eBay.
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