Yeah I have avoided using the internal brake assignment in CLS2sim. Connecting a USB cable to the pedals and assigning the brake axis directly there works fine. Lose one more USB slot though.
Manu, if you can’t get the axis to show up in the sim, have you connected the yoke and pedals together using an ethernet cable? You need to make sure that it’s connected from the 0-port on the yoke to the 1-port on the pedals. Both devices need to be connected by separate USB cables.