If it's using a lot of GPU resources, make sure VSync is checked in the settings. Depending on what version of the game you have, there may be an uncapped frame rate without VSync.
If Windows is flagging it as a virus, try downloading it through the itch.io app. That seems to help.
oh, alright, also when will you update this game by the way since i think its been like that since i first saw it (please tell me theres no 4 dollar dlc in steam)
