Logitech trackball issue in PSE

I use a Logitech Trackball with PSE 9.  My OS is Windows 7.  With the Logitech setup application I have the left button set as select and the center button set as drack-lock.  When running PSE the drag-lock button will sometimes loose the drag-lock function, requiring me to exit PSE and re-run the Logitech setup application to re-enable the drag-lock function.  My Windows 7 hardware shows this Logitech trackball as the only pointing device and therefore, I assume the default pointing device.  Any Ideas for a solution?