I purchased Civ 3 Complete from Steam about two years ago. I created a custom scenario that reversed the direction of global warming (desert turns to plains, plains to grassland, and grassland to tundra). This did not work, so I turned these changes all back to their defaults. However--even when I initiated a nuclear winter--global warming only worked insofar that it eliminated forests and jungles. No other terrain was affected (which really peeved me as someone who always loved the whole earth-turns-to-a-vast-wasteland as a consequence to using too many nuclear weapons ). Does anyone have an idea as to how to fix this?