Yes indeed - it 'only' predicts the elementary particle masses. Isn't that enough, though? And I find it fascinating that the masses depend on a set of eigen-values. Soon, a mathematically rigourous derivation of these crucial eigen-value equations will be published by Heim's colleague and successor Walter Dröscher and his collaborator Jochen Häuser. They are about to collect a prize for best paper submitted this year to the one of the propulsion committees of the AIAA (Aerospace academic society). So, it could be the year that Heim theory takes the world by storm, as a string theorist once wrote to me.
Hugh.
May the forces be with you - including Heim's 2 extra ones