here's a video displaying the issues i found (it goes over the upload limit so its a google drive link):
https://drive.google.com/file/d/1uwCQN2ALomfP14W4_NNgJyU6RlxDKFmj/view?usp=sharing

incase you cant tell whats wrong from the video, vent trapdoors always make nearby vents be open even if not oriented correctly, getting into the vent requires clipping inside the vent trapdoor, you cant get out (without breaking the vent itself), climbing doesnt work, and you cant re-crawl after standing up inside of them.

also the changes you said you made in #download are just completely false

it appears i was using the vents wrong since there was no indicator i had to click the actual vent block with the vent trapdoor on it (not click the trapdoor) to use them correctly