Is there any direct relationship between Teacher's Personal Markbook and the Motorised Markbook?
No. The original Motorised Markbook (see page 4) grading program was released by the New South Wales Board of Studies for the Apple II computer. That is going back more than a few years and if you are not old enough to remember the Apple II, it was a very popular computer back in the late 1970s and the 80s. This is before Windows and Mac systems dominated personal computing.
As a teacher in the 1980s the head of SMPCS had the opportunity to use the Motorised Markbook, but as it was clear that the popularity of the Apple II was in decline and the new PCs based around the original IBM PC were on the rise, work was done to develop a similar sort of markbook and gradebook program that would instead run with DOS and later Microsoft Windows.
So while there is no direct link between Teacher's Personal Markbook and the Motorised Markbook, TPM was developed during the same time period and based on similar ideas. Although at no time have the two programs had a compatible file format or menu structure.