i tried using this but it didn't worked:
CB_SETMINVISIBLE = 5889
hWnd = DialogControlGet(handle, dropDownName, @dchWnd)
result = DllCall('user32.dll', long:'SendMessageW', long:hWnd, long:CB_SETMINVISIBLE, long:5, long:0)
You can change the width but you can't easily change the height of the dropdown list part of the control once the size is set at creation. Haven't tried but you could theoretically change the height of the list by changing the font. However, that more or less defeats the purpose.
ok thanks!