Even if you would convert those maps, the hl game would proberly not recognize waypoints or coordinates for the AI, which leaves you running in empty maps without exit points
That is exactly what I thought.
Another thing is that the computer should load sound files(like dialogues) in certain situations in events, like when you first meet someone.
Another thing is loading scenarios, like that reconnaissance thing that opens the portal in hl1. You are supposed to do certain things in order for that to work, and you also need the files and the coding for when and where they will be loaded.
I am talking about a full scale HL SP experience with Goku instead of Gordon