Yes, that is right. You can still input speeds in knots, just ME writes converted speed (in m/s) to Dynamic weather file.
Previous versions of ME did not make conversion, so wind speed in mission was incorrect - roughly two times higher. For example: if you filled wind speed 2 - 6 knots, you got wind speed 4 - 12 knots, because 1 m/s equals to ca 2 knots. That was fixed in ME 1.1.7.8.