The load swatches command is for loading swatches from other documents or from a swatch file.
Use the new swatch command to add a color.
Thanks Bob! I'm also using the Adobe Color Themes.
You can add swatches (one at a time) from those ACB files, by choosing New Color Swatch from the Swatches panel, and then in the dialog box, select the desired file from the Color Mode menu, and then the specific swatch.
If you want to load a group of swatches, choose Load Swatches and pick an ASE file or an InDesign document, as Bob said.
Thanks JM! I'm so used to the quickness of selecting colors with PS & Illustrator, I thought ID worked the same. I'm getting familiar with it now :-)