We hypothesize that visuospatial knowledge alone is sufficient for analogical transfer of problem-solving procedures. We developed a theory of visuospatial analogical problem-solving. Proteus, our implemented program, provides a content account, with vocabulary and data structures, and a process account, with methods and algorithms. Proteus addresses all major subtasks of analogy, and identifies a new subtask: dynamic mapping generation between the intermediate knowledge states in the source and the target, when a step in the transferred procedure creates a new object. Examining the limitations of use of visuospatial knowledge alone, we help identify the functional roles of non-visuospatial knowledge.