Dear Frictional (some advice)

[MsHannerBananer]

In that particular area:

Spoiler below!

Within the security room (when you needed to fix the elevator by uploading data to the chip) you can unlock and lock certain doors. Therefore, you can trap the proxy here. I'm not too sure if you can trap any others in other places.

Fun fact! I was locking and unlocking some doors to try and make it easier for me to remember where to go in that area. As I was leaving, I was just about to open the security door, then the enemy was right there. I crawled back over to the computer and tried to lock it out, then I locked it in the security office with me ;-;

Rom, I think what the OP was saying was that even if they DID completely lock the Proxy in a room, it was finding a way to magically teleport out of it.