In my case (debian etch, java 1.5x, reprap host 0.8.3, arduino with no electronics attached and firmware upload from arduino11)
all the options show the corresponding window. Sometimes "Maintenance positions" and/or "Extruder exerciser" are crashing the
host software.
With no arduino connected there are error messages for a missing connection on /dev/tty/USB0
Sorry, my software is not really up to date, had some tries with libswitch and host 0.9 (0.9 seems not to work with java 1.5x)
and lost fun quickly. This configuration is everything I need at the moment, there are still some reprap hours to spend outside my
computer