I just installed this on a new eMac and to begin with had the same problem as everyone else - the Fax-Printer wasn't recognised and didn't appear in Printer Setup. However, then I re-read the installation instructions and noticed that you have to do things in the right order.

You MUST switch off and disconnect the printer first, then restart the Mac (just to be sure) then reconnect the printer and THEN switch the printer on. Now if you run the Printer Setup Utility you will find the Mac has found your Brother printer and all is well. Note, you only have to do this the first time, from now on the printer is always found.

It's worth the effort because this driver package is waaa-haay-hay faster than the standard Brother drivers - especially for any print-job with a lot of images. The prints fall out of the printer literally seconds after you send them, whereas the previous driver would churn endlessly before printing.

Try it again...

(BTW, I'm using this with a Brother MFC-8440)