After some tweaking, I got Legacy 6.0 (all builds) to work on Leopard, but it took some doing.
First, the only version of Crossover I could get to function was Crossover 7.0 (I have Professional). All other versions were giving me an active X error when the installer for Legacy completed, and then the program would bail, sometimes locking up my entire system to the point of a hard reboot.
I made a Win98 bottle. I then installed DCOM and Windows Media Player. Media Player installs just about everything, including fancy new versions of IE and Outlook.
I then installed Legacy version 6.0. Works perfectly now.