Hello. I have a question. If I'm in the middle of a game, and a person leaves, that deletes 1 computer. Is that legal? or I have to do another one?

I don't see how someone leaving changes the rules. You can see on several runs, like my Solo% Run in Abandoned Facility. Though reading what your saying, I never seen a PC get deleted in the middle of the run, so I'm suggesting you mean the beginning of it.

Yeah, i meant that. The beggining of the run. So if there's only me and the beast, there are only 2 computers and if I finish the run that can count as a PB.

Basically, but it can be kinda rare without friends around. (Still possibly a frame too so it's still hard, but slightly easier I guess)