Updated June 2013; see History
This flag allows alphanumeric keystrokes to act as "accelerator" keys, automatically selecting and clicking on the matching control, if present. You can define an accelerator key association for a control by inserting a "&" in front of the desired character in the control's text. For example, a button defined using "E&xit" will use "x" as the accelerator key. (The & will not appear, but the subsequent character will be underlined.) In this case, hitting "x" will have the same effect as clicking on the button.
Note that the standard Windows keyboard accelerator formula (alt+key) does not require that EVW_ACCEL be specified.
History
2013 June, A-Shell 6.1.1354: When the EVW_ACCEL flag is set, underlining of the hot keys is now forced on. Previously, and otherwise, it follows the Windows convention, showing them if the last input event was a keyboard event and hiding them if it was a mouse event.