So to begin the application isn't registering the majority of my steam library. I understand that the CORES wont show a game if its not owned by you however, I own all my games and they run using steam, with the exception of SIEGE which runs through ubisoft. However CORES has no problem detecting this game and then running it, in addition to the title ULTRAKILL and WarHam-40k-DT. I have not encountered errors when trying to manually add items and libraries, but it is extremely tedious to add one game at a time. as of posting this the version for CORES is 1.9.9 .