ps3000_open_unit() is the open unit function for the older 3000 series devices and will not work with your device, it looks like you may have the wrong SDK.
If you have access to a powered USB hub I would suggest connecting that to the machine that doesn't work and then connecting the adapter into the hub. If that scenario works then it is the laptop not supplying sufficient power to the USB port.
There does appear to be an issue with measuring the duty cycle when it is offset from zero, as in your case. As the development team are currently working on measurements I thought I would test against a pre release version which will appear as a Beta shortly and it does measure duty cycle. Keep an ...
When you have a set up you like go to File->SaveCurrentWaveformAs and change the type to pssettings. This will create a file that you can click on to launch the program with the desired settings.
If you are still have problems please send in details of your generated signal and the scope settings, the easiest way to do this is to post a psdata file.
Version 6.6.42 was a release candidate version of the software that did not make a full release due to a few issues reported back to us. These were fixed in the 6.6.46 release candidate which has now been upgraded to a full release. Can you try this version and let us know if the issue still exists....
I have managed to run your psdata file, having modified the save file location and removed the trigger, and it falls over at the same point for me. I have passed the information onto our development team and will report back when I have an answer.