adding data to the employee absence schedule template

Hi.

I have downloaded the Employee absence schedule template. I am trying to add extra colour coded boxes to the legend at the bottom of the template, E.G. yellow box for Staff Shortage. I have used all the available boxes and I cannot find the formula on how to add further boxes with more data. If I copy an existing box and change the name, when adding the code to the calendar the corresponding colour does not show up.
Excel sheet.PNG

Thanks

Upload sample excel file

Employee absence schedule1.xlsxEmployee absence schedule1.xlsx Hopefully this explains what I'm trying to do.
Thanks

I need to add extra boxes (Color key) with additional info? I too have the same issue...help?

Could someone please explain how they were able to add more options the "Absence Key". I am in the same situation and would like to add more than what is currently on the template. Any help with this would be greatly appreciated! Thank you!

I didn't see a post for a solution for this questions. Were you able to figure this out?