Setting up Chess960 Mode in Arena Chess Simulator?

Hello.

I was just wondering if anyone knows how to set up the Arena Chess GUI so it can analyze moves for Chess960 games?

I download the pgn files like usual.  Load it up and try to analyze moves, but half the time it doesn't work and says illegal move.

Or it works but like is all messed up and the output is something like a bishop moves like a rook now.  Weird stuff like that.

Anyone know how to do this? 

Arena is broken for Chess960: it uses a non-compliant notation for castlings, not used by any UCI engine. But you can use the Polyglot adapter to make UCI engines pose as WinBoard engines, (or of course use native WB engines) and then it might work. Not sure if Arena would allow you to use the more-advanced analysis methods (e.g. excluding moves from analysis) on WB engines, though. (And in any case you would need to use Polyglot 2.0.1 for move exclusion to work; 1.4 does not have that.)

I guess you would be better off to simply use WinBoard or XBoard, where you don't have to mess with adapters yourself when installing engines, but can symply tick the 'UCI' checkbox.