to recreate:

• in preferences be sure that Tiled Center Row and Tiled Center Column are enabled
• in graph make sure the visibility of Tiled Center Row and Tiled Center Column are disabled
• open a file and let it graph
  -then in the graph, enable the visibility of Tiled Center Row and Tiled Center Column. But they won't appear

if you enable the Tiled Center Row and Tiled Center Column visibility before graphing, then they show as expected.