@sgillies .. yesterdays FREE Ninox Webniar covered this topic.. :)   Not sure if they record / post them for review. 

You can manually set the "with color" option..  Note.. this effects the Ninox calendar only.. not the mac calendar. 

You can also "style" them via the Show As..

Yes you can, I have Mac app too, as @Mconnen told you...

For example: code for the "Show As" box

if Choice = 1 then
styled('Calendar Display', "green", "")
else
styled('Calendar Display', "blue", "")
end

@Nick I tried with your code in the “Show As” box, but it shows “function is not defined: styled(appointment,string,string)”

Prova così:

if Choice = 1 then
styled(“”+“Calendar Display”, “green”, “”)
else
styled(“”+“Calendar Display”, “blue”, “”)
end

@sgillies@mac.com What Mconneen meant re: “... not the mac calendar.” was that whatever changes/styling you made or make in Ninox (on the calendar), those would not appear in or make any changes to your Mac Calendar app. So if you made one of the colors bright purple in your Ninox calendar, you won“t see bright purple in your Mac Calendar app too. :-)