It depends on the OS you're using, but an educated guess is that you use Windows because of the way you ask
. Just download the savegames and walktrhough archive from the first post -- check if it is the same version as the game you installed. Now use the Windows executable. We asume that users of other OSses don't need this help
. Now start the game and use load game or autosaves in the main menu. The first give you two, first is mom path and the second is the neighbor path. Both at the end of the previous version, so you only play the new content.
With the second you start at the end of the loaded version. So loading v007 of the neighbor path places you at the end of that version. So you can play all new content after that.