I had to select the edges shown below on all of the feet of my model in order to give them a 0.1'' fillet, but for some reason they were VERY difficult to select.



It didn't matter if I had hidden lines displayed or not, my ability to select the edges that I needed seemed very finicky and dependent on my view angle and zoom, as well as mouse position. I tried it in V1 and there was the same problem, although it might have been slightly less so. I've since changed my design to no longer include the feet, but I still attached the file to see if you can reproduce the problem. Thanks.