You can save a pick list as follows:
Once you have clicked and dragged all the items you want in your list, click on the View In Main List button. This creates a search made up of the kuid numbers. Open the Search window and Save it with a unique name. At a later time you can click on the named search, then click and drag the whole lot into the Pick List window. You can add to or remove items and save it as the same name.
Hope this helps.