Glue Tool causes problems with Cross-Fades

My Use Cases for info. I record solo piano with a Left and a Right Hand channel (two separate microphones). I then edit my recording to remove the bits I don’t like and then piece together to create my final version. As part of this process, I use cross-fades between events. I had noticed that when adjusting cross-fades on later edits, it often moved the audio event a little thereby spoiling the previous edit. To get around this, I decided to ‘glue’ an edit to ensure once I was happy with an edit, it wouldn’t get inadvertently modified. However, I have then noticed that the ability to do cross-fades is removed (both greyed out in the menu and the ‘x’ shortcut doesn’t work.

I’m sure others must have come across this and I guess I am doing something stupid somewhere. Help would be gratefully received. Thanks