A 1542 release gives up known and uknown claims against your employer. Unless the agreement expressly provides that you cannot file an unemployment claim, 1542 would not prevent you from so doing. As a belt and suspenders position, you can ask to have inserted a provision that states: "Nothing herein shall prevent employee from filing for unemployment compensation. Employer agrees not to contest employee's right to seek such compensation."
The response given is not intended to create, nor does it create an ongoing duty to respond to questions. The response does not form an attorney-client relationship, nor is it intended to be anything other than the educated opinion of the author. It should not be relied upon as legal advice. The response given is based upon the limited facts provided by the person asking the question. To the extent additional or different facts exist, the response might possibly change.