> Is there anywhere to add the fact that I have registered as a user, some
> sort of list to add my presence as to how many of us there are in total?

You can add your keyfile no. and purchase date to that thread:

https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=5875&forum=14

Furthermore, there are several sites collecting data on MorphOS (and other OS) users. See there for the links:

https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=6395&forum=3&start=6
https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=6395&forum=3&start=19
https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=8087&forum=3&start=68