Vista 32bit -
7:07:28 PM : Allocating 1,380.44 Mb of memory
ERROR: Not enough memory for this render!
7:07:30 PM : Rendering terminated!
All well and good (despite having 2400MB available at the time), but when it terminates, it does not release the memory.
Windows Task Manager shows a commit size of 2GB.
The only solution is to close Apo entirely and restart.