CT:CE is a fan made game, created by average everyday people with a little too much time on their hands. They based their story on the original Chrono Trigger and Chrono Cross, for what appears to be a good story line. I will tell you that the story takes place five years after the defeat of Lavos, to say anymore may give too much away. You can expect some new Tech attacks, and the enemies are much stronger than you'll be used too, also weapons are few and far between. Overall the game is fun and worth the download. Have fun...
Also please keep in mind that this game is completely in every way fan fiction and is not associated with Square Enix, however Square Enix does own the copyright to the name, game, and all characters (as well as everything else) within.