Edit with Control Panel or FTP files to Host?
 

I'm a newbie to vBulletin, but I've been a C, C++, C# software developer for about 20 years.

On a forum that I'm a member of, the owner asked me to come in to spruce it up a little. He set me up with his administrator password for the site, and I went in.

Wow! Everything looks so awkward! It says we are using v4.0.1, but until I get him to send me the email address and license number for his product, I have to post here.

I downloaded the latest help file (vBulletin 3.7), but I can't see on here how to edit basic things like our site's logo, background image, etc. Should I be FTP-ing into the Host site to get to these?

Also, there doesn't seem to be a way for a newbie like me to *test* a feature. The site is live, and I really don't want to test out on the live site. Are there ways to play around with this?

I guess I need a crash course!

Extra Question: I noticed that now I have the ability to *change* a person's username. What does this do? Does it really change their username or does it switch all of the existing data to the new field? Example: Say I'm looking at JonDoe's profile, and I modify it to JD01 - does all of JonDoe's information save over to JD01 or is it copied into a new record called JD01? These are the kinds of things I do not want to simply experiment with on a live site.