http://puu.sh/awn12/1153c0bb97.dmm
Gets this error:

The map is 1000x1000, with 1 Z level. There are two other maps, but this is the one which causes the error. The issue is not unique to this map, however, because if I add a large number of objects to the other Z levels the error will still eventually occur. Originally I thought that the reason the error occurred was because of the object limit, but after discussing it with Ter we've concluded that it is a BYOND bug in the way DMB compiles its map data.