Put an image object (not an imageField) onto the canvas. Populate the image with the graphic that you want. Size it the size that you want (make sure to choose to embed the image data. Now get a button object. Lay it over top of the image (it will cover the image). Resize the button to the same size as the image. Now on the object palette of the button change the appearance to Custom set your Border Edges to None and your background fill to None. The image shoudl now show through but the caption for the button is still there. Double Click on the button and the text for the caption will be highlighted. Remove it. Put your code on the button and test it.
Paul