I don't know if this is still an issue for anyone, but I have stumbled on a rather odd circumstance where I can make this rubberbanding happen at will.
I have been messing about with AutoHotkey and remapping keys, and completely by accident, I discovered that if I remap my mouse wheel to the letter 'a' instead of its default scroll motion, the cursor rubber bands to the center of the game window.
When I start the game, the cursor behaves normally until I use the mouse wheel. So perhaps if anyone who has this issue, could test out my theory to see if their cursor behaves normally until they use their mouse wheel, it might give WGT a pointer as to what might be the problem, if it still is a problem. : )
EDIT : When the rubberbanding occurs for me, if I use Alt + Tab to switch the focus to another Window, then the issue goes away until I switch focus back to the game window and use the mouse wheel again.