It's a sad day when two consecutive posters on Telltale's forums are unaware of
ScummVM.
As for being like Day of the Tentacle, I HOPE NOT! My own personal feelings about the game aside(I very much dislike it), its ideas about puzzle-solving do NOT fit in a Back to the Future game. The puzzles in Day of the Tennt usetacle require a couple things:
1) Fairly constant use of time travel, and
2) Someone in another time period to receive an item,
3) Time travel being thought of as "the solution" to most problems
4) Fairly wacky and cartoony logic.
This doesn't work. In Back to the Future, only ONCE is an item "sent to someone in the future", and that's a letter that waits for Marty from 100 years prior not to get him to come back in time, not to get him to solve any problem, and not to affect the timeline in any meaningful way, but simply to make sure that a good friend doesn't worry and DOESN'T go back to affect the time stream. Doc Brown wouldn't accept a Laissez-Faire application of time travel as a solution to the minor problems that might come up during an episode, Back to the Future is a film franchise that has a more "realistic" approach than cartoons(time travel and the TV cartoon excluded). Generally, you go back in time, and being STUCK there is the problem or you have to solve a problem IN that timeline once you get there, or you have to UNDO changes made by another time traveler, but time travel ITSELF is almost never a direct solution, and when it's used that way it never works the way it is supposed to.
Essentially, yes, both franchises are TIME TRAVEL stories that feature an OBJECT that is modified to TRAVERSE TIME. But their APPROACHES to time travel and how it is USED narratively couldn't be MORE different.