When I'm coding a Greenfoot scenario, e.g. piano, I'd like to print the source code to have it better checked. At the top of the window are some menus, like class, edit, tools and option. When I choose class I can see "Print...". I pressed that. Then a little window appears: "BlueJ: Print source code. When I press the "ok" button nothing would happen.
I might be easiest to open a file directory and go to the scenario folder. Then select (right-click) the .JAVA file of the class in question, select "Edit" (open with a text editor) and print it from there.
I get a Print dialog box (after clicking on the "OK" button) when I try what you said you tried.