This is a PDF file I use for reference when I code, it has virtually everything included in this game (although some unique features are missing). It has 365 pages of juicy, documentationy goodness, as well as a complete reference for all GUI controls, script callbacks, console objects, and console functions. A++ would highly recommend.
Note: Some features of TGE were removed in MBG, such as terrains and liquids. As well, other features were added such as the Marble. There may be a few discrepancies to the version of TGE that MBG was compiled on, but this works well for about 99% of scripting.
PQ in a nutshell