Hello.  We have a problem doing the most simple thing with VRPN, which is tracking just one light on the head to move you through the world.  In our old code we simply wrote:
	Code:
	viz.go(viz.PROMPT | (viz.HMD + viz.STEREO + viz.TRACKER))
if viz.get(viz.TRACKER):
	PORT_PPT = 1
	viz.cursor(viz.OFF)
	viz.mouse(viz.OFF)
	ppt = viz.add('vizppt.dls')
	#Average over 5 samples
	ppt.command(5,'',5)
	isense = viz.add('intersense.dls')
	viz.tracker()
	#Set eyeheight to zero since we are getting it from the tracker
	viz.eyeheight(1.9)
 That is all we had to do. 
I tried replacing it with this:
	Code:
	vrpn = viz.add('vrpn7.dle')
ppt = vrpn.addTracker('PPT0@HOSTNAME', 0)
 Where hostname is the ip of our PPT machine.  However, nothing tracks - ie the person does not move through the world.  We don't get errors, the person just does not move.
Any ideas?
Maria