Me. Rev. Stat. tit. 14, § 7485

Any fact found or issue adjudicated in a proceeding under this chapter may not be deemed found or adjudicated for the purpose of any other cause of action. The judgment obtained is res judicata as to the amount in controversy. If a plaintiff has reduced the amount of a claim or contract to meet the jurisdictional limits of this chapter, the judgment obtained is res judicata as to the full amount of the debt or contract in controversy. The only recourse from an adverse decision is by appeal.