I believe the red boxes were put into place to have a visual type aid for those commands. Before people were clicking on them by mistake and did not know it and some did not even know about them.
As for the ESC to bring up the main menu that used to be included into the UI (to disable it via the eq2.ini file) but was removed from the UI when SoE added it as an option in the game options menu. You can now set the option yourself if you do not want it to open when hitting ESC.
As stated above don't quote me on anything here since I am not the author of the UI just a UI fan. I hope this helps..
