Why is the Apply button grayed out in the Search Results window?
The button is disabled when you search from a window in which Apply has no meaning (recipe select window is one of these). If you search from the Meal Plan window, Apply puts the selected recipes in the selected meal. If you search from the Print Recipes window, Apply puts the selected recipes into the print queue. If you search from the Export window, Apply puts the selected recipes into the export queue.
