I have taken Cephalo's excellent PerfectWorld2.py script and have added some more knobs to it; more parameters can now be tweaked from inside of Civ4's GUI. It is now possible to change the amount of oceans, the number of islands, how quickly the maps are made (with a quality trade-off), and whether to use a random map or a fixed seed from the GUI. In addition, I have improved the rendering of toric (donut) maps.
To install the script, copy Totestra.py to the PublicMaps directory, which should be at /Users/yourname/Documents/My Games/Sid Meier's Civilization 4 Complete/PublicMaps or somewhere similar.
For support with Totestra.py, please use this thread:
Please do not email me or send me personal messages that discuss this map script.
Please note that while Cephalo has given me permission to make my fork Totestra.py available, he is still the copyright owner of this file.