There are 4 of them, 2 of them for the regular pano, and two other are for top pano if I am correct. So, only two of them are used, depending on what pano setting you want.
It seems translucent water show less artifacts. However, lake water is causing it to be a bit more visible and that is the one I am using. When I add regular scene capture cube there are no issues, there is something happening with the actual blueprint from the video I have downloaded it seems. Any chance you could grab it and check what is happening there, I really don’t know where to go. Thanks!
Here is the link: https://drive.google.com/file/d/0B5999tVBIaIwOHBfSE9wdW56Unc/view