Three fan projects turned into three pages
Zeus gets a saved-game format page and a page on the limits of a big city; Emperor gets a page on how the original runs.
What came out of them
The Zeus Limit Patcher reads and rewrites Zeus saves, so its source is a map of the save container: a 300-entry manifest and compressed blocks, with six tables identified. That is the first written spec for any Zeus file, and it replaces a hub row that said none existed. The same code gives the table sizes behind Zeus's city limits.
Yongle, the Emperor display layer, hooks the running game, so it had to learn how the main loop, the clocks and the screen modes work. Its source is the first public account of how Emperor runs. Its loader for the .sg3 pictures also gave the SG page a second reader, and one question about the transparent colour that the page now records.