I am clicking the icon on the right of the bin line -- but only "Sky is the Limit" bin opens (repeatedly).

No problem creating a new project bin.

A screenshot would help.

Normal. This is not a button to create a new bin but to open a new tab.

Button for new bin creation is here :

 

thanks that works

Page #15 of user manual.

what is that right icon then used for ?? (other than opening "Sky is the Limit" ?

I already explained that it opens a new tab.

Once opened you can select a category in the left panel that will be displayed in this tab. For example some transitions or some titles or a bin or a collection or videos, ...

Tabs are described page #14 of user manual.

Another tip : hover your mouse over a button and a tooltip should be displayed telling you what action is done by clicking this button.

Tooltips are described page #3 of user manual.