Very well. I don't feel like creating another diagram, but hopefully this will satisfy your curiosity:

The room has one door, one window, one closet and one bed. There is other furniture within the room, but I guarantee the rest was not used in any way that would allow someone to hide, escape, or commit murder. It would be tiring to have to declare that every lamp, end table or shelf wasn't a hiding place for a human culprit.

You already have Rudolf and Gumshoe's descriptions of the door. The window opens up to the second floor, but it might still be possible to escape that way, so I'll add this: The window was locked from the inside.