It allows you to draw new sectors and lines in 3d mode, so you can have a very good idea of how things will look in-game, I'm not completely used to it yet, but I can confirm that it works well <!-- s:) --><img src="{SMILIES_PATH}/orc2.gif" alt=":)" title="Smile" /><!-- s:) -->. It's a bit buggy, but what can you expects of a beta? <!-- s;) --><img src="{SMILIES_PATH}/orc9.gif" alt=";)" title="Wink" /><!-- s;) -->