Button is the name of the button.
Panel is the name of the panel.
X is the horizontal coordinate of the button's upper left corner.
Y is the vertical coordinate of the button's upper left corner.
Width is the button's width.
Height is the button's height.
The position (x and y) is relative to the client area of the panel.
You don't have to specify x, y, width or height. You can set them later, after the button has been added, with SetWinPos, SetWinSize, and SetWinRect.
<AddButtonToPanel MyButton MyPanel>