What kind of venue was the conference in? Do you run into the same issue after moving back to your main work place?
I would recommend checking the tracking settings to see if Auto-orient tracking is enabled. Were the hands oriented incorrectly every time you started the application regardless of the controller orientation?
How much open space did you have in your booth at the conference? To minimize interference from external factors, we usually recommend keeping the area in front of the user clear of objects.