After conquering 1 planet and reaching the metal-planet, i started building there. Soon i was able to construct catalysts, but after the 3rd one (my energy was at -70k but that shoud just make it slower right?) whenever i wanted to biuld something an explosion appeared (one for each chosen unit). Anyone knows if it's normal or what i did wrong?
Make sure you don't have anything built too close to the spot where Catalysts are supposed to be. Also, I noticed that Catalysts are buggy and it takes a little mousing around to put them in place.
It actually sounds a bit like you had built way more energy storage than energy production the whole game while slowly accumulating energy. Then when you started building the catalysts (probably with lots of fabbers), everything was fine until you ran out of energy. If you are out of energy, but you have lots of fabbers, the game has to proportionately spread the energy income you do have to all those fabbers, and if there isn't enough to give each one at least 1 per tick, then those things will fail to build. That's the theory I have anyway xD.
Are you sure there aren't any enemy units attacking the catalysts? Do you have the free energy mod by any chance? (If so, it might be at fault)