Like J. Stephenson (issue 90) I too have had problems attaching the Brother M100 printer to my Sinclair QL: however, I found the staff at Brother very helpful.
A phonecall to Brother revealed that dip switches 1 to 8 should be set as OFF, OFF, ON, ON, ON, OFF, OFF, OFF.
The following morning I received from Brother a factsheet detailing the settings to be used in the install has program to allow articles written on Quill to be printed.