I'm not a big fan of the nextstar myself but others seem to love it. Anyway, as mentioned, lateral balance isn't a big thing for just flying around during training, it trims out. It does show up during stunt flying though so you may as well start the hobby by making lateral balance part of your set up for all planes. I just use stick on wheel weights like CG mentioned to the wing tip of the light side. I usually don't bother removing them and then hiding like others do on a trainer. Trainers are a tool and I don't bother trying to keep them pretty, they don't stay that way long after my students are finished with them.