I have categories in my gallery, but I don't know how to put new items in the categories hey belong. The new items go to the main category and I didn't make that main category. THANKS

All items automatically go into the main category (which you can't remove). You have to go into your gallery and click and change the category dropdown next to each item (the category name will be 'none' if they aren't in a category). Then save (process prices and removals) at the bottom and you're done. c: