dungeon.ppt slides on Google Docs: Elvis doors, DM attention markers and all. The first slide has all the symbols as grouped objects and the second slide is a how-to, with tips and a sample mini-dungeon that you can steal and modify rooms and passages from. The format is MS Powerpoint 2007 for Windows (.pptx).
The main innovation over the previous series of posts is a way to show unusual ceiling height - deviations from the usual 8 or 10 feet - with lines above or below the room number.
If you use this and you work in inches, let me know how the inches/cm conversion goes. My suspicion is that the background grid might be a little off for large scale inch-based work, but otherwise the .5cm = .2 in rule seems farily handy. Also let me know if you convert the symbols to other media, for example, Photoshop or CC brushes. Powerpoint is not a perfect graphic system and I think there's at least as much interest in the symbols as in the PPT implementation.