Following error new installation Pi5 stepper motor mill

Hi

Background. Taig 3 axis mill with stepper motors. Been running for about 10 years. Was PC based but PC failed.
I had  Pi5 to hand so bought HAT from byte2bot and a breakout board.
I used the HAL file and ini file from byte2bot modifying with information from the old PC ini file and setting pin allocations to match Pi.
just starting setup sorting out home and limit switches. X axis works perfectly but when I try Y axis I am getting a following error fault.
I understand the basics of following error on a servo machine. How can you get a following error on a stepper drive and what do I need to do to solve the issue? FERROR set to 1.
 Are there any other sample Pi5 HAL files available to download?

Regards

Ian