The images look great when opened. You might want to revisit your workflow as you're not creating sRGB for the colorspace in your images posted.
I've seen this stated many times by you and others and assume it's true. Linda has also made that point to me on a couple of occasions (even once fixing my thumbnail for me). But I always wonder why said thumbnails look OK on my computers (all three of them). His butterfly thumbnails look just fine to me. What am I missing here besides better vision?