The "parameters" button should not display any window since options are only available in Thunderbird.
But it is strange it hangs... Could you tell me if your mobile runs under Windows Mobile 2003 or 5.0 ?
I could reproduce the problem. When pressing the Settings button, ActiveSync hangs. If you wait 30 s (yes it's long ), it stops hanging. I know the reason of this behavior but I don't know yet if it will be possible to fix it though...