Hmm. That could be either the imp of the perverse, or possibly there is a figure or prop (or content provider) in common with the crashed scenes? Others have had issues with which version of the waveform format a .obj was outputted as. Back up the scenes in question and start deleting items one at a time, starting with whatever background props you have, and see if you get a good render. There could potentially be an issue with a texture as well; there are python scripts out there that set all materials to nothing, so you could do that on your test scenes, and if you get a successful render, then you have your area to search. If it still bombs, proceed to the prop deletion process.