Didn't read all the replies, but the kitchen footprints do not look like blood. I am not even so sure about the garage. The garage splatter pattern is odd though for any reason that readily comes to mind in term of bike trainer accident. In my line of work, I see a lot of blood every day and this looks a bit manufactured. I am sure that we have a slowtwitcher that works in forensic science that would know more than I though.