Maybe a Rebuild & Regenerate would help? Do this by holding down the Alt key when accessing your Rebuild menu item.
Brief run down on Rebuild & Regenerate:
What you see on the display (the lines, fills, textures) is stored in a database. When you modify something on the screen (edit an element or zoom in, etc.) you actually modify this database. A rebuild makes these modifications appear on screen. Of course, Editing, zoom, etc. automatically triggers a rebuild, so usually you do not have to initiate it manually. If you hit rebuild, you make sure that the display is coherent with the screen database. It usually clears the type of errors when you move something and it does not show, or there are ghost lines that should not be there, etc.
Rebuild and Regenerate throws the screen database away, and builds a new one. If you hit rebuild and regenerate, you avoid the type of bugs that fail to refresh the screen database. It usually clears the type of errors when a change in the settings or elements' parameters does not show.
Cheers,
Link.