When I post a reply, the previous messages in the thread are listed below it in center justified mode. I don't recall it doing that before?

There are two ways to reply... if you notice, each post in a thread has a "Reply button that is a quoted reply to that post. At the very bottom is an "Add Reply" button that simply adds a fresh reply to the bottom of the thread. You might be using the "Reply button on the last post instead of the "Add Reply" button at the very bottom.

Another interesting item of note is that if you select the "+Quote" button on multiple posts and then click the "Add Reply" button at the bottom, it will quote all the selected posts for you (useful when applying an in-depth rebuttal to a discussion).

Let me know if you want anymore clarification on it. It's a new system and it just does some operations really differently.

Both buttons behave the same way - center justifying the text in the previous messages in the thread. It's not broken, just hard to read.

I haven't figured that one out yet either. I wasn't really worried about it since it didn't seem to hurt anything, but if it's hard for some to read, I can look into it.