In the event of default in the payment of principal of or interest on an investment made, the authority is authorized to institute proper proceedings to collect matured interest and principal; the authority may, after consultation with the board of directors of the authority, accept for exchange purposes refunding bonds or other evidences of indebtedness at interest rates to be agreed upon with the obligor. The authority, after consultation with the board of directors of the authority, is authorized to adjust past-due interest or principal in default.