At the time of making any final payment of compensation, the employer shall be entitled to a final receipt for compensation, executed and acknowledged or verified by the worker, which final receipt may be in form a release of liability under this act, and every such final receipt for compensation or release of liability or a copy thereof shall be filed by the employer in the office of the director within 60 days after the date of execution of such final receipt or release of liability, and if the employer shall fail or neglect to so file such final receipt or release of liability, the same shall be void as against the worker.

The director shall accept, receipt for, and file every agreement, finding, award, agreement modifying an award, final receipt for compensation or release of liability or copy thereof, and record and index same, and every such agreement, finding, award, agreement modifying an award, final receipt or release, shall be considered as approved by the director and shall stand as approved unless said director shall, within 20 days of the date of the receipt thereof, disapprove same in writing and notify each of the parties of his disapproval, giving his reasons therefor, sending a copy of the same to each of the parties by certified mail, return receipt requested. No proceedings shall be instituted by either party to set aside any such agreement, release of liability, final receipt for compensation or agreement modifying an award, unless such proceedings are commenced within one year after the date any such agreement, release of liability, final receipt for compensation or agreement modifying an award has been so filed and approved by the director.