[SOLVED] White cross in Compositor with Viewer node (2.65a)

I get a white cross in the Compositor when I add a viewer node.
And it doesn’t update the Backdrop or add glare to my sun when I add a Glare Node.

(EDIT: Solved. The reason it didn’t seem to update was because my Glare Node’s Threshold was set above 0. Also I need both a Composite AND Viewer Node connected to the Glare’s Image).