I think we have the same starting position, because there's not much choice in this map. Yeah, you have to be careful with your energy, and the spores are a big energy drain. I messed up a few times when spores came at the same time (for the first waves I used 5 beams, after ~11 minutes there is a wave where I needed 6, and after ~22 minutes there is are 3 waves arriving practically at the same time, there I used (and probably also needed) 9 beams). That went wrong a few times. Attached you'll find screenshots how I did it. I'm very interested if you used a significantly different strategy than mine in some aspects.
@Godsbrother: I'll try that map out, sounds good!