This question relates to Art of Reading, so relates to Bloom and WeSay, but also the full AoR collection (DVD)
Art of Reading contains line-drawings, but some books need color images. (This may be a requirement for books created in association with specific organisations).
If someone takes the Art of Reading images and colors them (digitally), how do they handle the copyright? Is SIL International still the copyright holder of the images? Do they just keep the same copyright year? Do they just put a note about who has colored the images?