Dom I maps can be found under downloads at
www.illwinter.com I believe.
To make them useful you must remove the color dots at the top of the map. Otherwise there will be a province in the upper left corner of the world.
You should probably rescale the map as well, or add the line #defaultmapzoom 3.0 (or something like that) in the map file.
One important thing. The provinces are numbered differently, so old specials must placed in new provinces if you would like to keep them.
Also there are no terrains or province sizes in Dom I. All provinces from a Dom I map would be treated as plains of normal size, unless you reedit the map.