Since the first major game released by Techland Chrome all games using the proeprietary ChromeEngine offer to the enduser an easy way to modify the game scripting, by taking the java code and modify it to there needs.
Until I find a easy way to import hundreds of java files into this wiki you may visit http://fallout.bplaced.net/chromeengine/ for java source downloads.
The codebase is laid out in an easy to understand folder structure for easy modification. An example for the game Chrome using ChromeEngine 1
Altough Techland took great care to ship there games with full Access to the java classes up to the game Xpand Rally. There has been low to none modding activity in the community. One of the few mods created where “Reg 8 Player Mod” for Xpand Rally (Basicaly only a one line code change) that lead to a patch by the developers to adress mod loading issues in the dedicated server. And a now defunct mod for Call of Juarez called ”Version 220.127.116.11”
Since Xpand Rally Xtreme the developers no longer ship there games with the java classes or offer them for download on the interweb. One has to decompile the compiled java files to gain access to the code. Which leads to no directory structure and no source comments.