Not sure what's going on without seeing the image or stim list files. Try the revision I've attached and see if that helps. Also, try taking any path info out of your stimlist files. e.g., Instead of something like:
C:\Documents and Settings\Monica\...\stim1
C:\Documents and Settings\Monica\...\stim2
Just use:
stim1
stim2
Also, make sure all your stimuli and stimlists are located in the Stim folder that is located in the same folder as your input file.
If that doesn't help you, try zipping and attaching your stim folder.