Adjustment layers...how to get a border/outline for the whole layer....

Yes, you can add a border or stroke to your adjustment layer to make it more visible. Here's how you can do it in :Select your adjustment layer in the Layers panel. Click on the Layer Style icon at the bottom of the Layers panel (it looks like an "fx" icon). Choose "Stroke" from the list of layer styles. In the Stroke dialog box, you can adjust the size, color, and position of the stroke around your adjustment layer. You can also check here for more decortrendy  choose whether the stroke should be inside, outside, or centered on the layer. Click "OK" to apply the stroke.

If you want to add a drop shadow instead, you can choose "Drop Shadow" from the list of layer styles in step 3, and then adjust the settings to create the desired drop shadow effect. By adding a stroke or drop shadow to your adjustment layer, you can make it stand out more clearly against the layers below it.

Not how adjustment layers work. You would simply use a normal solid and apply whatever effect to it, setting it to render on transparent so the source pixels disappear. You can even apply a matching full size mask to it with a simple double-click on the shape tool icon and obviously resize that. Point in case: You will need an extra layer one way or the other.

Mylenium