I believe I understand how to embed a single google calendar no problem. I simply goto settings > select my calendar > click customize > and then I can customize how I want it to look. I know there are many examples of how to do this part. Please read further for how I am having problems with more users for the embedding tool part.
I am trying to have one calendar combine two other gmail accounts. To make it simple, I will call my combining account, account A and the other two accounts I want it to pull from E and C. I have successfully added them to where I can view them together when just going to the default calendar view:
However when I goto the embedding tool, I don't see the second calendar (listed as C in the first image) as an option:
Notice how the "E" email address shows up but the "C" one does not.
So how do I get calendar "C" to show up on the embedding tool?