I have image to display when I do mouseover on column header. But imp thing is it should be display below columnheader area.

I am able to create that but's it's overlapping with below cell. Here is image.

Some how my rowheader is working. my row header width is 36 and close button width is 28 with left margin 26. and some how image is no overlapping there with cell

Pls use this link for code and image:

Pls help me to fix. Thanks Dee