The Max travel setting is found in the Focus module under the Mechanics tab. For a value, try determining a range of steps from the focus position that does not produce donuts and set it below that. That should prevent it from traveling too far from focus and be capable of recovering.
INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
Waveshare Stepper Motor Board - DIY Focuser
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.