I can't figure out why I have an object (light-grey ellipse) that cannot be selected by selecting the layer and clicking CTRL, or why the object doesn't even show up in the Paths window. I can Ctrl + T to move the object or whatever, I just can't get the marching ants around it. Everything else seems to be working OK. I can select the other object (black circle) that is on the same layer.
I had tried turning off the layers one-by-one earlier to see where the light-grey ellipse resides and it "is" on the same layer as the selectable circle. This is not a 3D workspace -- the image is a result of following a tutorial on simulating a 3D effect by painting an object with various brushes. I don't recall rasterizing the object or the layer. I created the object by dragging out an ellipse with the marquee tool and then painting in it while the marching ants were still active. The tutorial showed how to lock the transparent pixels on a layer, so from then on I used this method. I unlocked everything before trying to select the light-grey ellipse.
It may be a layer style that you have rasterised. Ctrl Clicking will not select it because of the low opacity. If you want to remove it select the layer in the layers panel then just drag a rectangular marquee around it and, ensuring the layer is still selected in the layers panel, use Edit > Clear.