Played it again, now I figured out how to get through doors (step back a little)! Here's my new feedback:

• The game has the vibe of early 90s shooters; "Collect the keycards, fight through guards / drones and get to the exit". Simple, but effective!
• I liked being able to shoot and destroy walls!
  
• I haven't found a reason to use the Loop Mechanic, I understand it's a restart?
• Currently the Loop Mechanic is bound to the R key. I wish a different button than R was used to start the loop. Most shooter games have R as a reload button, and even though this game has weapon auto reload, I caught myself pressing R frequently after a fight (habit), only to restart the fight I just finished
• Very minor, but I expected the assault rifle to act more like an assault rifle instead of a shotgun / bolt action rifle

Either way, I'm happy I gave it another shot. If you're into oldskool shooters, you could like this one!

I could not open the first door. Despite using F on my keyboard, the door remained closed. I was completely stuck because of this I could not play the rest of the game.