Each product in my cart is unique - i.e. there is only 1 unit available. So I want to hide (or make read-only) the quantity field on the products list and checkout pages. Currently when I check "Hide Quantity" in module settings it hides the quantity field on the products list page, but if I add product to cart then all the quantity fields reappear.

The "Hide Quantity" setting in the BuyNow setting hides the quantity on the Product List page, not the cart page. I was able to verify that when you have the "Quantity" and "Add to Cart" hidden on the product list page, clicking "Next" page at bottom of product list causes the "Quantity" field to reappear. I have forwarded this issue to programming.

Christian