I finally figured out the texture problem:
the culprit was in the windown initialization code:
Code:
othrPOV = viz.add(viz.VIEWPOINT)
othrPOV.translate(0,0,3.4)
PinP.viewpoint(othrPOV)
PinP.visible(viz.OFF)
I had switched the last two lines , so vizard didn't like hiding a window and changing its viewpoint.