FTPRush provides a wizard to let you customize main interface on the fly.
To use this wizard, click on "Help" of main menu, then select the "FTPRush wizard.." from the dropdown
menu. click on "customize main interface.." from the popup window.
The wizard will teach you how to customize the interface step by step.
There have some screenshots of customized interface as below.
Office2003 style in WindowsXP theme mode