Deleting Cuelist from Master Cue Error

Hi, I'm just learning to use this software, and I'm self-teaching. I've read/watched a lot of tutorials, and I've done a lot of online searching/reading. So far, my biggest draw back is still removing things from the Master Cue list. I'm following all the steps in every combination I can think of, but the only thing that works is a Clear All from the page options. I've hit [Delete] and the [Master Cue #], but they won't come off. Any ideas? Another step I'm missing? Making sure x, y, and z are cleared or on first?