You can't make custom commands on an old-school server, as you would need to code them in. If you do manage to get an old-school v1 emulator that is open-sourced, you would be able to.
Me and my friend have tried setting up this RP hotel, and the client just turns white, everything is up-to date, but it's just not working.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html...