Currently menu key mapping functionality in 'Preferences' has following issues:
1. If a selected accelerator is already assigned to a menu, an error message is hown but user is not given a chance to apply it. When applied the acceleartor will be de-assigned from the old menu and will be assigned to the current menu. For default menus do not allow shortcut change or sharing.
2. TAB character can be part of the accelerator. In accelerator text field user cannot type tab character. Provide a button named 'Tab' to enter TAB.
3. A menu can have multiple accelerators, but these can not be shared by other menus.