When I launched the game exe for the first time, I was in for a surprise: First intro vidoe, second intro video, then a black screen with a white arrow, and nothing else happened.
ALT-TAB'bing didn't let me switch to a different window. but showed me that there was a firewall alert message in the background. After a while the main game menu appeared, and the game seemed to work normally then. The firewall alert message had disappeared. When I looked up the firewall rules, I noticed that there was a rule letting the game exe access the internet. Blocking that access doesn't seem to affect the game functionality.

Unfortunately, I couldn't see the IP the exe was trying to connect to, so I can't say for sure that the game is really trying to send data from my PC to the internet. But I want to pass the information about my experience with this game on to everybody who doesn't like external software to take control over his / her PC behind his / her back (without my firewall I wouldn't have known).