It is possible to make smaller maps, but the smallest one is about 75x75. I made this mod for you with these map sizes: 75x75,100x100,125x125.
Here is the link to the packed dll: https://mega.co.nz/#!eYdn0R5J!UphFDG9O5-6ahIriHJN4ASNz92Ma_t7iyOK2LCegd6w
Here is the link to the packed dll: https://mega.co.nz/#!eYdn0R5J!UphFDG9O5-6ahIriHJN4ASNz92Ma_t7iyOK2LCegd6w