Although colours are customisable in some areas they do not flow through in all areas, which affect ability to use colours that could clash.

One instance Student view: absence button appears in bright red, even after we have set other colours for student logged absence and lecturer logged absence.

It is such a strong colour and unchangeable in settings, so it dictates and limits the rest of the colour scheme applied. Ie. we must design around it. See eg of what cannot be a scheme.