You don't add the line.. you modify the existing one. It's at the bottom. probably you have a ipx=true line, and then later on an ipx=false at the bottom. So its like you turned it on and then turned it off again within the config file.

I've also noticed this. I can play Transport Tycoon Deluxe in dosbox just fine. The moment I click the button that makes the game attempt IPX stuff, it practically dies in speed. Oddly enough, the MIDI music in the game is normal, whereas the midi music would normally slow down if I started dropping …