I have tested today, and if you write the line as it is in the docs, it will only launch the Display utility and not parse the image filename to the utility. Putting double quotes around the whole command will execute the command properly, thus parsing the image filename to the utility. When using spaces in the filename, you will have to do as I posted earlier, so
@{"Picture of a Workbench Screen" SYSTEM "sys:utilities/Display \"sys:This is my Workbench.pic\""}
Testing was done on real hardware with OS3.9. Multiview version 45.9 (2002/01/18)