This is my go-to calendar app. It has THE BEST and most sophisticated engine for scheduling recurrent events. Version 5.0 (issued Jan 24) has fixed the color coding bug. You now have the option of activating color coding through the settings tab.
However, the "updated" (messed up) interface is still a step backward compared to the older versions. The ruler lines under the scheduled items are gone in the weekly view, which makes individual items harder to read. Individual days headers used to be nice black contrasted ribbons, which are no longer there. Please at least give the option of reverting to the old interface to those of us who preferred it that way.
The original Hachi Cal actually had the nicest week view layout interface. The current version of Hachi Cal 2 has now fallen behind its main competitor Week Cal.
iLux Lucis about HachiCalendar2 Pro, v5.0