Problem with Bitmap layer


I’m now using a trail version of Storyboard Pro 5.1 and I’m having a trouble drawing on bitmap layers. As in the screen-cap I attached, I can only draw on vector layers but anything drawn on a bitmap layer is not shown in the Stage view window. It appears normally on a thumbnail on the layer tab.

Another thing is that I cannot see any brush and texture samples on the brush properties window. Is there any solution for this problem?