Paintbrush mode is interesting, as is the tiled layout as opposed to the hexagons.
We were / are under the impression that the Red tiles shown as "Target" here stood for "Taught" at least at some point in the past?
I'm glad you like the look and functionality of the markbook.
There is variation in how different schools, and different frameworks, approach the markbook colours which is why you are able to customise the language used on them. The default terminology is 'Target'; while many schools do choose to interpret this as 'Taught', others use it to mark a pupil's next step(s) which many not have yet been taught.