Ok, was wondering why a lot of systems wouldn't let set up a space station. Thanks for clarifying that for me 
My knowledge ever increases 

I cleared out revs in a system but it wont let me build any stations in it. It says there already built but i couldn't find any on system structures. I didn't see any anomalies so i dont think the station is cloaked. I was able to mine in the system, but i cant build in it. (Building already constructed in this system! Click on structure image to acccess commands.)

So im kinda confused.

Ill start with the easier questions and then move on to harder ones 

Q1: What are all the known formulas for ship components?
Q2: How do you determine the total ABS for multiple shields? (Ex, having 1, 30% shield ABS and 18, 15%)
Q3: Is figuring out the total ABS for multiple shields the same as figuring out the total ACU if there are multiple computers?
Q4: What is the difference between Relative and Total Attack power? In battle does it mean that 100 ATK with 25% ACU only does 25dmg each shot, or that there's a 25% chance to do 100dmg?
Q5: If i have multiple weapons on one ship, is there stats combined?

Yeah there toughies, but things i hadn't been able to figure/find out yet.