When you use starch, make sure you use the fabric right away and don't store it. Silverfish and other buggy critters LOVE starch!
Another online group I belong to recently had this discussion about whether or not to prewash. One of the members there does some kind of work in the shipping industry and said she ALWAYS prewashes because she is well aware that a lot of the shipping conditions include exposure to rats and their feces. I know the fabric comes wrapped in plastic and packed in boxes, but it still gives me the heebie-jeebies!