Love the generator. 

Question: Is there any way to change the type of terrain in a specific area? (ex: make a forest a desert)

This looks like an amazing time. This is going on the top of the list of rainy-day one-shots.

Looks like its down. Is there a mirror anywhere?

I love this! Thanks so much for sharing your work with us all!

One "small" request: Would it be possible at some point to be able to set the desired population? 

I like that you included population density, but I cannot find an option for population count.