If a prj.conf file was selected in the Generate Build Configuration screen, it was not possible to deselect it. We have now added an option to the drop-down menu that represents "no prj.conf selection", which will cause west to perform its default behavior.
We have also addressed an issue where the Edit Build Configuration form would default to the Compatible boards or Nordic boards selection, which might not contain the board associated with the build configuration being edited. We now default to All boards when editing.