I found a kinda big memory leak when loading the colony summary in a loaded game.
When generating a summary it goes up in ram usage (obviously as it loads much stuff) but when closing the ingame summary window and opening it again the game starts hogging even more ram.
On my game it goes so far that it uses 14GB opening it the first time, 17GB the second time and 24,5GB the third time where it stays.
When going back to the main menu it clears of most of the ram usage.
I attached screenshots from taskmanager, savegame and dxdiag file but there was no output_log.txt.
I'm using the build LU-358820 which I downloaded from Steam
Maybe something faulty with giving free space when closing summary.
Open a game that you have played for a while and open the "Colony Summary" a bunch of times and check in taskmanager how much ram it uses each time