That "patch.bat" file, when run, copies "Capture3.j2l", "Jazz2.exe" and "Race1.j2l" to "C:\Games\Jazz2 Xmas99". So apparently it expects you to have CC99 already installed in "C:\Games\Jazz2 Xmas99", but it changes the Capture3 and Race1 levels, and something about the game's executable file. What the differences are as compared to the original versions of these files? No idea.