I think you’ve already done this but the full install is as follows.
git clone https://github.com/pimoroni/fanshim-python
cd fanshim-python
sudo ./install.sh
cd examples
sudo ./install-service.sh --on-threshold 65 --off-threshold 40 --delay 2
Once that is done the fan will be off until the on threshold temp is reached.
And stay on until it goes below the off threshold.
I couldn’t get the manual override to work. I think its one long press of the button to switch to manual. Then a short press for on, short press for off.
Another long press puts it back to automatic. For me the fan would switch to manual mode, but pressing the button just made it spin for a second or two and stop?
There is a thread on here somwhere.