I don't really understand how the shop/upgrade system works in Really Big Sky. For example, Wideband, the first item, seems like a one-time purchase item, as it allows you to fire 2 shots at 45 degree angles.
However, when I go to purchase it, 20 points are taken away from my total there, and the cost in star bits goes up to move further across the band. Do I have to completely purchase the entire bar before I receive the upgrade? Or are further purchases just upgrading the potency of that item?
Can someone explain how this is supposed to work? Also, do the star bits I don't use carry over, or do I lose them? I've currently been trying to upgrade as much as I can when I get there based on the assumption that I lose them if I don't. Is this the case, or should I be saving them?