I had a kmaps update on my todo list, so that's out now. However, there's a change in the dir structure.
I had noticed earlier that there were some different keymaps with same names (e.g. both qwerty and dvorak versions of no). So this time kmaps.tcz mirrors the structure from kbd, type/map.
tl;dr the path is now /usr/share/kmap/qwerty/fi-latin9.kmap.