Hello Tricia,
I would recommend using the latest build because you are using version 1.1.518 of Nixie, we are now at version 1.1.563.
Then use the webgui instead of the swingui because some it's functionalities are not supported anymore.
You will need to use CHROME as default browser for the webgui.
Anyway functionalities buttons between webgui and swingui for openCV are rather similar.
But in webgui, most buttons have an explanation text when hovering with the mouse, which helps to understand what does what.