Greetings to all, as this is my first post!

That said, I am working on my first map using Jeremy Elford's tutorial for an antique style map (which is designed for photoshop). I have my base map in black and white and am just starting to go through his second section on antiquing. Where I'm running into trouble is creating a new alpha channel (I did manage to get a duplicate of the original alpha), and copying the map layer and pasting it into the new alpha channel. When I try to paste it into the alpha channel, I get a floating selection (pasted layer) as a new layer and can't select any other layers.

Any help I can get is much appreciated!