We have a road with both a stutory road association and part of it is not --governed by the State Statutes.  How do we include the persons who are not in the statutory group to become members in the road association.  Is it the case that just by living on the road you become a member with a right to vote?

Statutory Road Associations are governed by 23 MRS 3101-3104.  Section 3101, subsection 2, defines the members of a statutory road association as follows:

2.  Call of meeting.  When 4 or more parcels of land are benefited by a private road, private way or bridge as an easement or by fee ownership of the private road, private way or bridge, the owners of any 3 or more of the parcels, as long as at least 3 of the parcels are owned by different persons, may make written application to a notary public to call a meeting. The notary may issue a warrant or similar written notice setting forth the time, place and purpose of the meeting. Copies of the warrant or similar written notice must be mailed by means of the United States Postal Service to the owners of all the parcels benefited by the private road, private way or bridge at the addresses set forth in the municipal tax records at least 30 days before the date of the meeting. The notice must inform the owners of the planned meeting's agenda and specify all items to be voted on, including, but not limited to, all proposed budget items or amendments that will determine the amount of money to be paid by each owner pursuant to subsection 5. Subsequent meetings may be called in the same manner or by a commissioner or board appointed at a previous meeting pursuant to subsection 5.  

So anyone who owns property that has a right to use the road for access is a member, and should be assessed for dues.  It is up to the road association members to decide their formula for charging dues, so long as that formula is "fair and equitable" - which the Courts have so far taken to mean that whatever criteria you decide on, you must apply it in the same manner to all members.  In other words, if you decide that everyone pays the same, them everyone must pay the same.  If you decide that year round residents pay one rate, seasonal residents pay another rate, and undeveloped lots pay another rate, (or even pay nothing until the lot is developed,) then that formula must be applied to everyone in each of those categories.