1.  Recording.  The declaration, any amendment or amendments thereto, any subsequent declaration, the bylaws, any amendment or amendments thereto and any instrument by which the provisions of this chapter may be waived, shall be acknowledged and recorded and shall not be of legal effect until duly recorded in the registry of deeds of the county in which the units lie. Such instruments shall be indexed in the grantor volume under the name of the building and shall contain a reference to the file number of the floor plans of the building affected thereby.  

2.  Revised declaration.  After the original declaration or a subsequent declaration of the bylaws contained therein has been modified or amended a total of 5 times, the board of directors shall prepare a new revised declaration with revised bylaws attached thereto, incorporating all modifications and amendments to date, which instrument shall be recorded forthwith.  

3.  Floor plans.  Simultaneously with the recording of the original declaration there shall be filed in the registry of deeds of the county in which the units lie a set of the floor plans of the building showing the layout, location, unit numbers and dimensions of the units, stating the name of the building, containing a reference to the original declaration, the date thereof and volume and page of recording and bearing the verified statement of a registered architect or licensed professional engineer certifying that the floor plans are an accurate copy of portions of the plans of the building as filed with and approved by the municipal or other governmental subdivision having jurisdiction over the issuance of permits for the construction of buildings. Attached to the floor plans shall be a survey of the land upon which the buildings and improvements are located. Such plans shall be kept by the register of deeds in a separate file for each building, numbered serially in the order of receipt and designated "unit ownership." In the event the floor plans are modified, new floor plans shall be prepared and recorded, containing all the identifications and references of the original floor plans, numbered identically as the original floor plans, filed therewith and designated "unit ownership -- floor plans modified (indicate date)." A floor plan need not be prepared or recorded of any building which contains only one unit.  

4.  Conveyance of any legal interest.  Each conveyance of any legal interest in a unit shall be recorded and indexed similarly to the conveyance of any interest in real property. No instrument conveying or purporting to convey such an interest shall be effectual against any other person but the grantor and his heirs until duly recorded in the registry of deeds of the county in which the unit lies.