Will someone please tell me... If I am using the same images, the same image filenames, file size, etc. as are on my product manufacturer's site will that count against me as duplicate content? What about SKU, descriptions, etc?
It will count against you in Google Image Search yes, just like regular SERP's Google Images don't want to serve up a page of identical images for a query. As for regular SERP's then no, the important thing is your text content such as product descriptions being unique.