On Mac OS X you can hide the buttons on the window title bar with our plugin. With both FileMaker and Xojo (RealStudio), we have code in next prerelease.
For Real Studio and Xojo we have an example project to disable or hide the buttons.
For FileMaker we have our normal functions to disable the buttons which will now hide them also.
Sometimes it is good to disable the buttons to disallow the user to close the window while some process is running.