What happens when you just try a simple script connecting to the intersense. If you look through the device manager you'll see which COM ports are available. Verifiy that you have a COM port 3 and set the PORT_INTERSENSE variable to 3 before you add the intersense
Code:
import viz
viz.go()
PORT_INTERSENSE = 3
isense = viz.add('intersense.dls')
If that does not work and you have other COM ports showing up try changing the PORT_INTERSENSE variable to the other values.
If you are still not able to connect check to see that you can connect to your intersense software.