They keep enhancing the engine as needed.
For example, they needed good fogging ability for Jurassic Park, so they added it. That wasn't in the tool for Sam & Max Season 3, or they would have fogged up the cloning chambers. After JP, Jake went back and posted a "Here's what it would have looked like" image showing the cloning chambers as they would have been rendered by the newer version of the tool.
So the answer is, the Telltale Tool can do anything they feel is worth programming in for a particular game.