If you can work with image files in the host, do you really need an equivalent in the guest? I only ask because I've got Photoshop CS6 and Photoshop Elements 6 (and much else besides) running in Mavericks, so don't want to duplicate files, apps and activities in 10.6.8 which I run in Parallels for other reasons.
However it is possible to view image files in guest 10.6.8 by getting all such files to open with a little app called File Viewer, though you can't work on them. I was tempted to install iPhoto '09 to see if your editing problem was evident on my Mac too, but I haven't found time yet. I could also install Photoshop Elements there too. However the quickest way to test it would be to download a very small image editing app called Seashore. If that too doesn't allow image editing, then something is very wrong indeed with Parallels in this regard and Maria (above) would be better spent devoting her energies to investigating that instead of merely reposting stuff from email to here.
ETA: i did download Seashore and edited a file with it and saved it as a new JPEG - seemed to work without problem.
Last edited: Feb 21, 2017