Pressing <Control Tab> to switch between modules sometimes works.
If I press <Control-F> to find the code and then arrow up and down it is not always visible, although it is there, as I have just found it with <Control-F>.
I wonder if this is a highlighting issue.
I have another NVDA Excel question: is there a way to stop NVDA speaking and displaying messages like "Cropped" and "Overflow"?