It isn’t possible to show products by Manufacturer.
It isn’t possible to find manufacturers by search end drag them to the right Category, like Product to Category.
It is already possible. Please make sure that you are using version 1.3.1.157 or later and that you enabled Manufacturer column in main products grid (see attached screenshots).
If you want to search by Manufacturer in Products Search - then select it in dropdown "Fields to search in" (see attached screenshot).