i had the problem with my 4-row LED cabindisplay, too. its a bit more complicated, because you have to use a few macros to get things done:
this is basically a duplicated form of the script already existent in ibis2.osc.
you can increase the value in the first line for the second, third and so on busstop. This will work as long as you have a valid route for your line, without the need for an active timetable.
the big one is the "actual" busstop, the bottom one is the second and third stop. you have to add a bit of code to prevent switching to the next busstop before reaching the stop itself. the string will change after triggering the next busstop in the IBIS in its current form..