How to downgrade to OS 3.1 from 3.2
Touchpad and CX/CX CAS:
Press and hold down [Doc] + [EE] + [Enter] and then press reset. You will see four options appear when the calc reboots. Select the first option and wipe the OS. Next, connect to your student software and send over OS 3.1, which can be found here. Now 3.1 is installed, so install ndless! You can also use this function to get your calculator out of an “ndless” loop.
Press and hold down [Home] + [Enter] + P, then press reset. Follow the same steps above.
Calculator stuck on loading screen
For all platforms, remove the batteries. This is a little harder with the CX and CX CAS, but a video of how to do it can be found here. Be very careful with the pins!