My 'Wobbly Windows' is not working

The problem is likely related to  "Show window contents while dragging" in Windows

Go to:

Control Panel -> (All Control Panel Items [View by: Large icons]) -> System -> Advanced System Settings -> Advanced [tab] -> Performance->Settings... -> Custom -> (6th setting from bottom, "Show window contents while dragging")

Check "Show window contents while dragging" and see if the WindowFX effect now functions.