Easy Grouping for Google Calendar

OMG! This is great! I have always wished for this. I wish I had found it BEFORE I retired!

Spent ages grouping the calendars and then can't open it as it immediately crashes. Disappointing as I would have loved this tool

At first I thought it didn't work, but then I found their YouTube videos (brief demos) and saw how to use it. Now it's extremely useful to me.