
running in opengl mode with quakespasm engine
And with Portal mod 

UPDATE: I uploaded the file to dropbox instead of 4shard so you no longer to sign inYou can download the game data here:
https://www.dropbox.com/s/rdhpzyxj2fry4iz/portal.zip (only dm7 map that is playable now)
Original Quake1 data are not needed!