The problem is fixed in the current update, but it can appear again, as some changes may trigger that reaction iteratively.
In this case the newer version of game's launcher is sent to the antivirus developers, which then is added into their database of safe files. While the file is being researched, you can add the game's folder into the antivirus exclusion list, so it won't spam you with the warnings. If the game fails to start after that, please try to download it anew.
Please note, that the antivirus message about potential threat doesn't always mean that the program is malicious. We haven't ever had any intention of damaging you computer, just bringing you pure fun and entertainment.