What OS and version of Elements are you using? Lowering the size of the file may not fix a problem with the actual resolution. What is the actual pixel size of your edited image? Does it display properly in the Editor? And are you just seeing the "grey image" in the Organizer? Take a look at this article about maximum image sizes. Try reducing the resolution of the edited image, using the Image>Resize>Image Size menu. If that does not solve the problem for you, we need more details (and a screenshot) of your grey image.