I had some questions come in that I thought I'd answer here for the benefit of everyone.

The first was how to add a response to the welcome thread. First click through from the main Emerson Exchange 365 page on the welcome thread hyperlink the "Getting Started" widget:
 

Next, hit reply to the top post. If you want to reply to someone else's post, such as to welcome them, you can also do that.

If you select "Rich Text Formatting" in the lower right, next to the reply button, you can add hyperlinks, pictures, bullets, etc (similar to Word). If you have additional questions, leave a reply and I'll answer, or find the answer.