I'm currently working on building a planet in Fractal Terrains. I'm using the earth settings for Physically-based Base Temperature (23 degree tilt, albedo = 0.3, 1 sun, Greenhouse = 1.1) with 100 cm/year rainfall and random amount set to 80. Fractal terrains seems to be unwilling to generate areas with a desert climate. I've created very large continents (11000km by 11000km) and have also generated and placed mountain ranges in such a way that rain shadows desert should form. The only way I've been able to get a desert to show without drawing it in myself was by lowering the rainfall amount to something like 20cm/yr.

I guess my question is, am I missing something that might cause FT to exhibit the behavior I need or do I need to place the deserts myself?