I'm posting this for philiptdotcom while I'm trying to figure out why he can't create new threads.

Adobe online instructions* say: "Do not select...vector layers....";
however, what I need to do is to (vertically) align a raster layer with
a vector (text) layer. How can I do this??? (A more simplified version
of what I want to do is to center-align a text layer within the
"margins" [left- and right-hand boundaries] of the document. However,
if I could align a text object to a raster object, I could achieve this
[by making the raster object the width of the document].) Please help!
Thanks...

*I'm a newbie, so it won't accept a URL from me; sorry that I can't
provide link to where I got this msg (on the Adobe support site)

I don't 100% understand your question, but it could be as simple as View>Snap, or View>Snap to...

See if either of those takes your fancy. Once they're selected then when you drag the image to somewhere near the middle of the page it will snap into place.

Or is this not what you're after?

If you use the Transform Tool (CTRL+T or CMD+T or Edit->Transform) you get the X and Y coordinates for the selected layer. Select Reference Point Location: Center-Center and then use the same position values for both objects (vector or raster doesn't matter). That should do the same as if Align Center actutally worked

Hmm... Aligning a raster layer to a vector...

Well mate...

Control + Click (Apple +Click) the text layer you want to align to. (Marching ants appear around the text)
Select the Raster raster layer you want aligning.
(Making sure the move tool is selected) USE THE ALIGN FUNCTIONS AT THE TOP.

And if your still not happy. De-select and use the arrow keys.

Was that so hard?

Or you could manually make a selection and align to that, which ever floats your boat.