Found it, and you were right to point at Area 4 as well. The tunnel walls behind Line 1 <Area 3> (and Area 4, plus the subway jump-quest rooms) repeat only every 30,000 pixels, and the game was building each of those ten wall strips as one giant 30000-pixel-wide picture. That is about a gigabyte of memory and wider than any graphics card can hold, so the screen went black, the walls never appeared, and your PC ran out of room. Those strips are now drawn as a few normal-sized copies instead: same picture, about a sixth of the memory. LIVE now (reload the game first). To re-test: walk into Line 1 <Area 3> and <Area 4>. The map should load in a second or two, with the tunnel walls and pillars behind the Wraiths instead of black. The Wraith and Jr. Wraith spawns there are the map's normal ones.