It's an old bug that never was fixed and has nothing to do with memory. One common source of this error is when Poser loads a figure or prop with external geometry and is unable to locate the associated obj file, then gives an "out of memory" message instead of telling that was unable to find "xxxxx.obj".

When Poser runs out of memory it gives no message, it only stop working or crash or its windows and dialogs begin to vanish and any other effect, but no "out of memory message". Probably you will need to restart the computer

Stupidity also evolves!