When you need to reach participants in different spaces, you don't always need to be moving between spaces. You can also chat between spaces.
Opening the chat
Select the 'Show chat' button in the bottom meeting buttons.
The chat pane will appear with the chat history of the space you're currently in.
Chat between spaces
While being in the Central Space, Kevin needed James for some clarifications on design. Instead of jumping out of the current discussion in the Central Space, he simply sends James a message in the 'Design' space.