FixedColumn Horizontal ScrollBar Doesn't work

Hi,
i'm using FixedColumn plug-in and it works without problems but the horizontal scrollbar works only if i press after the fixed column.
If i want put scrollbar on the left and i press it under the fixed column, the scrollbar doesn't work.
Why? Is it a bug or i am forgetting some options?

Now i can't post my website because it is on local machine.

Thank you in advance.

Marco