Questione giuridica chiave
Whether the cantonal court arbitrarily held that only a nullity complaint, not an appeal, was available against incidental exequatur in summary debt-enforcement proceedings.
Decisione estratta
The interpretation was defensible and not arbitrary.
Motivazione estratta
The cantonal provisions and preparatory materials did not clearly establish that appeal was open in this procedural setting; mere legal error would not suffice for arbitrariness.