I have downloaded and used the CD Slide Show Generator PowerToy for years. Recently, whenever I try to write pictures to a CD, I am no longer asked to add the Picture Viewer to the CD. I have already uninstalled and reinstalled the CD Slide Show Generator PowerToy several times, but in vain.
To reinstate the missing dialog, follow these steps:
regsvr32 shimgvw.dll
regsvr32 slideshow.dll
Restart Windows and check if the missing dialog box is reinstated when writing pictures to a CD. If the problem persists, here are some checkpoints to follow:
Using the CD Slide Show Generator PowerToy you can view images burned to a CD as a slide show. The CD Slide Show Generator PowerToy adds a CD Writing Extension (slideshow.dll), which prompts the user to add a picture viewer when writing image files to a CD. Here is how the dialog looks like:

If you choose the option Yes, add a picture viewer, it adds the files autorun.inf and autorun.exe to the CD automatically.