JUST TO CLARIFY: This is only true for images in which the first layer comp hides some effects (aka layer styles). If the first layer comp only involves hiding some layers, without hiding any effects, all is well. It’s not a showstopper (once you know about it) — it’s just One Of Those Things. This advice applies whether you’re using the image as button artwork, or just as static artwork in the InDesign document.
When you’re building complex Photoshop files, Layer Comps are a great way to store the visibility of layers that constitute versions of the image. For example, if Layers 1, 3, and 5 are Version A, Layers 2, 4, and 6 are Version B, and Layers 7, 8, and 9 are Version C, you can create three layer comps that let you access each version of the image with a single click. A Layer Comp can also store the position of layers, as well as the visibility of Layer Styles (such as drop shadows, inner glows, bevel & emboss, etc.). Layer Comps make it easy to keep track of versions while you’re experimenting, and when you want to quickly show a client those versions without trying to remember which eyeballs to turn on/off. 😉
Layer Comps can also be invoked by InDesign’s Object Layer Options feature, to control the visibility of layers and effect in placed PSD files; this is especially handy when you’re creating different appearances for interactive buttons. It was while creating buttons that I discovered a bug in the way InDesign handles Layer Comps. If you use Object Layer Options to manually turn layers off and on, all is well. My images had just one layer, but multiple effects (aka fx, aka Layer Styles) applied to the single layer. So I couldn’t invoke separate layers in InDesign, and had to rely on Layer Comps to control the visibility of effects that constituted each version of the button art.
I discovered that, unless you have the first Layer Comp in the Layer Comps panel list selected when you save the file out of Photoshop, you’ll never be able to reveal that first Layer Comp in InDesign. It allows you to select the Layer Comp, but ignores its settings and instead displays the layer comp that was selected when you saved the file. So you can never invoke the first layer comp in InDesign, unless it’s the selected comp when the image is saved.
As you can see in the image above, the first layer comp should just be the plain green text. But InDesign displayed the “Add Rocks” layer comp when I invoked the plain green text comp. Aaarghh (and, of course, it was late at night).
Moral of the story? If you’re relying on Layer Comps in InDesign, make sure the first layer comp in the Layer Comps panel is selected when you save the image, even if you think you won’t use it. It’ll save you the confusion and frustration that had me banging my head on the keyboard at midnight!