No .arena file is always a bad start. This map is saturated with items and small details that prevent you from moving around smoothly. The game play is fast and horizontal on either of the two main floors. There are a few missing textures and the level does not appear to be a full vis. Bots play a little too simply but they are otherwise fine.
Best to skip it.
Update: The download now includes an .arena file and a few other corrections. See the readme file for more details. (12.Apr.2003)