Adding colour to greyscale pics.

No problem but you get more chances to get quick reply on dedicated gimp help forum (i.e mail list as http://gimp-user-request@lists.XCF.Berkeley.EDU or sides as www.gimptalk.com) anyway first open your imagine and Image/Image mode/RGB. then just create a new transparent layer (Layer/add layer) on top And HERE the point change this new layer merging mode mode to "COLOR" that is basic Now you can add the color you like, they will not replace the grayscale under with solid colors (That will happen with default "NORMAL" mode) but just add the colors respecting the lights and shadows of the greyscale layer. You do not need to merge down when finish, first save as xcf so you may correct or edit more later...then save a copy as jpg or png (that will automatically save the visible merging ,in the jpg or png copy, the layers) but again this forum is basically for question on plugin hosted here,usually no much chances to get quick replies for general gimp help here