The links to the Mark4 and Mark5 firmware has been posted in the Direct Links thread. Please note that this firmware version has not been tested on a Touch N905C or Mini. Nor does there seem to be a Mark3 (Touch N905, N905B) version available.
See this post:
https://www.mobileread.com/forums/sho...&postcount=689 for the links until murg adds them to the first post in the thread.
Regards,
David