Trouble with the compositor

I understand that if you want the updated render or image in the compositor, you would press Control Shift and Left click on the “Render Layers” node. However when I do this the connections will randomly skip around and the image will become completely white or black. In addition, I’m not seeing any actual change to my picture when I change the hue and saturation.

Here’s the file:

And for some reason, even after packing external data, the backdrop won’t show up when I reopen the file, so I have to render it again to see it.