ОгнеярЪ
Auto-translated
I couldn't create a random map on Fix3. Moreover, I downloaded and installed Heroes of Might and Magic III Complete, then installed the latest February version of VCMI, and encountered the same error. I suspect that since the developers are still working on it (VCMI), and they presented a map editor for VCMI in January, they simply made a mistake somewhere. Overall, the solution seems to be to install the December version of VCMI (i.e., the one that was available when Fix2 was released).