Please make sure your drivers are up to date and check this list: https://wiki.palobby.com/wiki/Windows_Incompatible_Software (eg disable GameFirst) Then upload your dxdiag and some logs: https://forums.uberent.com/threads/how-to-find-the-pa-logs-and-game-lobby-ids.69151/
Please define "big system". Be careful with statements like "optimize game please" One way to optimise the game would be to add more limits on the size of planets/system you can create. Of course any performance improvements would be great.