§ 32. Certain liens and claims not to be affected. The amendments contained in this act shall not apply to mechanics' liens, building loan contracts, mortgages, assignments and orders referred to in section fifteen, attachments, judgments, or to claims or liens acquired in any action or proceeding upon such mechanics' liens, building loan contracts, mortgages, assignments and orders, attachments or judgments, filed, recorded, docketed, entered or obtained, or to contracts for the improvement of real property made, prior to the date when this chapter, as amended, takes effect.