First of all, I'm sorry that I'm a dork. I just realized that there are two different things going on here - earth points and weapon points. I was getting earth points and thinking they were weapon points, so there's actually no problem with the weapon points accumulating correctly that I can tell. While we're on the subject, though, what exactly are earth points for?
As for the difficulty, I personally think it's a lot more difficult than what I remember Earth Day on the PocketPC being. I seem to have to rely on smart bombs and the BFL too early on in this version. However, I do like the fact that you can accumulate more BFL points than what are necessary to activate the laser. That's a nice touch.