Legal Question in Family Law in Connecticut

This was in Connecticut? I'd have to see the decree, but probably you can file a contempt against the ex. Does the ex have the wherewithal to pay you?

You do have recourse. You can serve your ex with a motion for contempt. Of course, it is only worth the effort and expense if you think your ex spouse has the funds to pay the lump sum. Perhaps you could get an order that he pay it in a few installments.