Hi,
I am also not able to enter the gate after I entered the code (or I don't know how). The UI to enter the code is working after loading from a checkoint. I used the latest version 1.06 (Linux build).
Btw. can you maybe pause the game while entering the code? It's a bit frustrating if you are confrontated with an interface with text to read, while you only have one or two seconds to do something.