Adding custom models to UT3?

So recently I bought the entire UT anthology, and I've been having a lot of fun with UT3.

While fooling around with the character creator, I saw a button that suggested (to me) that there was a way for custom characters to be added to UT3. Sure enough, I found many custom characters, and I downloaded one.

But now I'm stuck- how do I get it ingame? All the tutorials I've found have been fuzzy at best and assume a bit of knowledge of UT3 that I don't have.

You need to put them in My Documents>Games>Unreal Tournament 3 iirc

That worked, thanks!