I have just completed a play through with all possible inventory items collected. I found only 2 problems. The 1st was that some doors previously opened by cards would remain open. I do not remember this happening in the original game. The second was that the boss music for the tank did not play the first time I reached it. I was able to walk off the screen, and then it would play for 1 second, then stop and go back to the normal exploration music. I died and the next time I reached the tank the boss music played correctly.
Was Schneider removed from this port? I never received any of his transceiver calls. This includes the call where he tries to tell us who is behind everything.
Cheers. It was a treat to play through this game on my Analogue Pocket!