OnMouseDrag not being called?

So I need to be able to tell when the mouse gets dragged up and down in my plugin. So I look in The example solution "IPlugMouseTest" and it has nice simple working code that detects when the mouse gets dragged in different directions, great! but when I implement almost identical code in my plugin the OnMouseDrag function never gets called! wtf? Here is my code Code:

Your method has the wrong signature. You should be overriding IControl's: Code:

Thank you! 

Can't believe I missed that, oh well I am a noob so I forgive myself. Thank you.