Having upgraded to newer versions of NX you may notice that the mouse scroll wheel direction has reversed to how it was pre-NX10. In previous versions you could set the variable UGII_MOUSE_WHEEL, however, this no longer works since NX 10.
The NX customer defaults now has an option to reverse the scroll wheel direction:
1) Select "File --> Utilities --> Customer Defaults --> Gateway --> View Operations"
2) With the "View Operations" tab selected locate the Mouse Wheel Scrolling "Direction" drop-down menu with options "Forward to Zoom In" and "Backward to Zoom In".
3) Choose the desired direction and restart NX to see the change.
Notes and References
OS Version: 764SP1