The utilitarian interior of the ship jives perfectly with Miller's 1970's concept of space travel, although he would have expected more cumbersome airlocks and tighter quarters. Han will indeed find the trespasser in the lounge area, where he's peering at panels of flashing buttons and desperately quashing the temptation to press them all. If he hears the approaching footsteps, he doesn't seem terribly concerned about hiding or looking contrite.