Right now, just open up conquer.exe in your favorite hex editor and check for the value "English" and change it to "english" press save and you have a multiclient!
The text around the one you want to modify will look somewhat like this
path_menutitle Dialog21
Spanish French
English
path_target path_bottom path_auto
Sound/BtnClick.wav
Change that so it looks like
path_menutitle Dialog21
Spanish French
english
path_target path_bottom path_auto
Sound/BtnClick.wav