Brian,
We deliberately used that condition - we only want to see updates by end users or those outside of the team. But one could easily substitute last updated user...
Mark - I agree with Chris - if testing this way you need to set a default query in Object Designer. Otherwise your code looks fine and should run OK.
For the pic we simply referenced two graphics (on our webserver) in the report, by putting in a pic URL to "address/{new-attribute}.png" - a transparent one called "-.png" and the one you see called "updated.png".
Happy to show you more if it helps.
Can't tell you how many people have praised this simple feature.
Sometimes the quick and easy tricks pay off....
Cheers - Adam.