the special ABS systems that you mention in the latter part of your last post relate to (for instance) the SBC (sensonic braking system ?) that the w211 cars use. These braking systems need I think a Mercedes computer unit that wires into the car to peform the flush or even brake pad changes, not exactly sure.

For your car you should be able to get a nice pedal feel by just evacuating and refilliing your reservoir to the very top, getting a good leak-proof connection from your Motive bleeder, and use a clear tube from the bleeder to a collection bottle with old brake fluid in it and the other end of the clear tube submerged, then open bleeder and watch old fluid travel out till it runs smooth with no bubbles. I actually place some Amsoil synthetic grease around the hose connection to the bleeder to eliminate as much as possible air traveling into system at that juncture.
You may have to disconnect Motive bleeder a few times to refill with fresh fluid as you go through the process. I'm not familiar with capacity of Motive bleeder.

You also have to pump brake pedal to press inward the pistons against the new brake pads before bleeding the system.