Hello, I like Boolean Modifier very much, but I had with this feature some of problems. For my needs I found a solution and now I can enjoy with Intersect, Union and Difference operations everytime without errors. There is short video, only 14 minutes, hope will be helpful. 
Very easy, for beginners, step by step: https://www.youtube.com/watch?v=3JAZsJv7vUE&wide Best watch in 1080p HD. Thanks for watching.