Trying to delete a simset causes T2D to crash

I'm having an intermittant problem trying to delete a simset in my game.

I create an animated sprite object, fill in its details, and then add it to the simset. I loop through this procedure several times to create a simset containing my enemy objects.

Then, when I leave the game to return to the menu, I want to delete all the items so I can start the next game with a clean enemy simset. The code I'm using to do this is:

if (isObject(WaveSet))
	{
		for (%i=0; %i<WaveSet.getCount(); %i++)
		{
			%obj = WaveSet.getObject(%i);
			%obj.safeDelete();
		}
	WaveSet.delete();
	}

To my understanding, this should loop through the simset, grab each item, queue it for a safedelete and then delete the simset. However from time to time T2D will crash with a 'T2D has encountered a problem and needs to close' message generated by Windows.

I don't know if I'm queing up too many safedelete operations - there can be upto 40 items in the simset when I iterate through it. Should I add a schedule to the WaveSet.delete call in order to delay it for the safedelete to take effect?

Or there is a different way I should be doing this?