Incorrect SubMenu Behaviour

The current submenu processing is not correct.

1) If a submenu is shown and then the cursor moves to the next element (causing the submenu to close) then the submenu item remains highlighted for a short time until the menu closes. This does not match the Microsoft menu behaviour.

2) It is possible to have two submenus on screen at one time. Normally one disappears after a short time, but on one occasion when using the Chevron (not reproduced since) the menu did not disappear.