Here are the level codes for the single-player maps:

Level:        Code:
1:            AMPORGE
2:            JOGRWAI
3:            GEGIDOS
4:            WABODAE
5:            BUFASWE
6:            GEHAUWA
7:            OLARIBU
8:            FITORGE
9:            DAFATWA
10:           WABIKDO
11:           GEEUSAT
12:           KAIMAWA
13:           SIETIBU
14:           GEDEROM
15:           ULUARGE
16:           ABUNDWA
17:           LANADGE
18:           WAFEFAL
19:           BUSALUG
20:           GEKEFZU
21:           YETUDWA
22:           WAGOPAY
23:           ZAFLUGE
24:           SKATZWA