go into apsfilter and <ln -sf> to the script step for paper size, and put an icon of your choice for it on the menu bar to call up the terminal. a pain, but it can work. sort of like an icon link to start up <link>
your best out would be to have 2 or more selections of printers (even tho you only had one) to choose from, each with different parameters, and functions. such as paper size. you still gotta go to the console.