Speaking to your first question - it is possible to get the product images via API. It is very hard for me to understand what you are trying to do from your question (a code snippet of what you have tried would be helpful).
From the Bigcommerce Ruby lib - you should look up this method. It will do what you want. T
def get_products_images(options={})
@connection.get("/products/images", options)
end
You will receive a response like the following -
{
"id": 5,
"product_id": 28,
"image_file": "sample_images/picture_1__48492.png",
"is_thumbnail": true,
"sort_order": 0,
"description": "",
"date_created": "Mon, 26 Oct 2009 05:08:32 +0000"
}
The store image can be found from http(s)://storeurl/product_images/{{image_file}}