That's really bizarre. Let me look up some possible causes and get back with you.

Just to verify something - do you have a controller plugged in? It sounds like the joystick is bring held to the left and fighting with your keyboard input.

If the cursor is snapping to the center of the screen, it definitely means the game think the controller is being pressed.

We have some wireless controllers around the office, so we can try to repro. In the meantime, would you mind restarting your PC with the USB receiver unplugged? Sometime joystick drivers can calibrate in a goofy way where they think they're being pressed when they're not.

Some games spawn a virtual joystick...was one of the tasks something called "VJoy"? 

Glad it got sorted out got really nervous for a second that we screwed something up with the input handler

Found this on another forum and copy paste it here if anyone has the same problem.

1) Go to Device Manager
2) Along the top select 'View' -> 'Devices by connection'
3) near the top of the newly organised list should be '3Dconnexion KMJ Emulator'.
Expand that by clicking the '>' arrow to the left
4) select 'HID-compliant game controller'
5) right click that entry and select 'Disable device'
6) Enjoy no longer having the SpaceMouse Enterprise getting in the way of other things.... like gaming in Steam for example.