Queue slots= It keeps the player aware if all the queue slots have been used (IE like starcraft with the numbers per available slots on the production queue).
That's not going to work exactly the same way, buildings have unlimited queue slots now. Instead, when you have multiple buildings selected, there should be an icon over the ones which are producing/researching something.
By default, chat is allies-only. Shift-enter is how you chat to everyone. (I had to figure that out by myself).