That is normal if the camera is using the DIGEST method for handling user/pass. Ignore it if the binding is working, as it is how digest works. If it does not work then this may be a clue, but I can not tell from a short snippet of the log without knowing more info. HIK cameras allow you to select BASIC auth and this wont happen and uses less bandwidth at a reduced security tradeoff.
The binding can create ‘snapshots.mjpeg’ streams for you even if your camera is not capable of mjpeg. It does this by using the snapshots so read the docs to learn more.
The older HIK cameras prefer the non ISAPI urls and some of the newer ones only work with the ISAPI version. If you click on ‘show advanced’ see your very first picture you posted, you can then change the URL used for the snapshot. The HIK camera also come with the CGI/API turned off by default, have you turned in on in the cameras own setup?
I don’t understand why you are asking this? you do not need to use motion detection at all with the binding and most features work without it. The features that are ‘complimented’ by having it are the autofps.mjpeg stream and also when you use the ‘group’ of cameras to display as a single view as the rotating display of cameras will jump to any that have motion.