Legal Question in Civil Litigation in California

You first have to look to the language of the agreement as to whether it gives a time limit. If not, the it is a "reasonable' period of time, which will vary with the circumstances. But the defendant can not choose to re-litigate the matter; a settlement has been made and the plaintifff can sue to enforce that contract asnd for any damages resulting from the failure to pay.

You now have a contract with the defendant, and you need to either file a motion to enforce the settlement -- did you make sure the court retained jurisdiction to enforce the settlement? If not, and the original case was already dismissed, you would need to file a new lawsuit for breach of the settlement agreement. Watch out for legal time limits.

Your post is confusing. You state that you settled the case out of court, but later mention "legal documents" with notes on them have caused delay. If the "legal documents" you refer to is the settlement agreement, and they have not been signed, you may not have a settlement yet.