Those commands will obviously fail if /dev/mouse does not exist, add
--create to the command line of settrans, so:
settrans -c /dev/mouse /hurd/mouse --protocol=ps/2
or
settrans -c /dev/mouse /hurd/mouse --protocol=ps/2
That should read:
settrans -c /dev/mouse /hurd/mouse --device=com0 --protocol=microsoft