Closed Loop speed control is a feed-back system where you command the motor to turn a given speed. There is a sensor attached to the motor shaft which gives a signal proportional to shaft speed. The actual shaft speed is compared to the desired (set) shaft speed, and the controller automatically increases or decreases the average current to the motor if it is running either slow or fast.
Sounds like you just want open-loop (no feedback, no sensor) control.
Do you want to use the HI/LO speed wires, or will you just use one or the other?