Hi! First let me say to you that I'm just starting to migrate from Parse and you have to work on your Guides. Parse is a lot more clear in most everything in their documentation. I think you should give examples right after you explain the code. Right now I'm having trouble getting the file url. This is my code:

var query = new Kinvey.Query();
    query.equalTo('nombre1', 'Dan');
    var promise = Kinvey.DataStore.find('miembros', query);
    promise.then(function(entities) {
        console.log(entities[0].foto);
        var promiseFoto = Kinvey.File.downloadByUrl(entities[0].foto);
        promiseFoto.then(function(file) {
            // entity.logo === file.
            console.log("foto url : " + file);
        }, function(error) {
           console.log("Error con url : " + error.description);
        });
    }, function(error) {
        alert("Error ENTITIES");
    });

 The "console.log(entities[0].foto) is giving me an object and I want the url of the file.

Dan,

If you figured out the issue, can you share it so other people could be helped?

I'm guessing that you were after Entities[0].foto.downloadURL ?

var promiseFile = Kinvey.File.upload(blob);
           promiseFile.then(function(file) {

             var entity = {
               nombre1  : nombre1,
               nombre2 : nombre2,
               apellido1 : apellido1,
               apellido2 : apellido2,
               correo : correo,
               rut : rut,
               bautizado : bautizado,
               discipulado : discipulado,
               direccion : direccion,
               telefono_casa : telefono,
               telefono_celular : celular,
               comuna : comuna,
               fecha_nac : fecha,
               mes_cumpleanos : mesCumple,
               ano_ingreso : añoIngreso,
               autor : usuarioActivo.username,

                foto: {
                    _type : 'KinveyFile',
                    _id : file._id

                }
              };
              var promiseS = Kinvey.DataStore.save('miembros', entity);
              promiseS.then(function(entity) {
                  console.log("Usuario agregado con éxito!");

              }, function(error) {
                  console.log("Problema agregando al usuario. Error : " + error.description);
                  
              });

           }, function(error) {
             console.log("Problema al subir la foto. Error: " + error.description);
             
           });

 The problem was that I wasn't setting the file._id