A. You can't zoom in to get a better look. I can hard wire in a different view if enough people think it's necessary, but I didn't have the higz-know-how to get a zoom to work.
B. You can't go back to look at earlier events. This isn't a display problem, it just has to do with how the engine steps through events.
C. Because of 2., you can't view coincidences. Note that you can start up another display (from a third terminal) and have it look at the other spectrometer, but because the engine can't go back in events, you can't look at the same event again. Note that this hasn't been tested extensively, and might not (probably won't?) work if we have a bunch of different people analzying and viewing events...
D. Every now and then, the blow up of the wire chambers on the perspective view won't show the track (that does show up in the full view). What can I say? GEANT works in mysterious ways.