I have a similar issue, although slightly different... I used to be able to happily click and drag by clicking and holding down in the bottom left with one finger on my left hand, whilst dragging with one finger on my right hand... but since updating bootcamp drivers to the latest version, it ALWAYS stops dragging and performs a right-click halfway through.
For instance I drag a window from the left to the right, but 7 times out of 10 it will stop dragging en-route and perform a right click. no matter HOW still I keep my left finger pressed and held.
Wish I could revert back to the old bootcamp drivers.