We recently had a requirement that the button sizes in OBIEE had to be increased. The reasoning was that the users of some of these reports are old and they hate smaller sized buttons. Now we know the properties of buttons such as the size are set in the css files which together form the skin. While it is possible to copy the skin and then edit the desired property, it is a long process.
This blog talks about a shortcut to achieve the objective.
I was recently involved in a project implementation on OBIEE 10g. The dashboard had a multiselect and the values in the prompt were huge. The standard width of the multiselect was making the user uncomfortable since a large part of the value was hidden due to the small size of the multiselect. This blog talks about a method to fix this problem.