Assuming there are models called "Index0" to "Index10", does this work or at least take the effect?

   a = 2;
   b = a + 3;
   SetThingModel(Index0[a + b]);

What was necessary for the above question to work?

(Lacking what will make the above question not to work?)

Do you think you can put cog verbs within "[" "]" brackets to concatenate as variables rather than just letters or numbers?