DVDA 5.0b and 5.2 hang at "burning lead-in," finally giving me a IOCTL error. I'm trying to make a 36 minute single movie disk (no menu) from a MPEG-2 NTSC widescreen file rendered with an unmodified MainConcept template in VegasPro11.0 64-bit. There are no error messages after preparing the file. I can successfuly burn the same project directly out of Vegas on the same system, using the same media, so I don't think it's a driver or media issue. I've tried moving the preparation file location to different drives. I've reinstalled 5.0b and 5.2 and the latest version of VegasPro 11.0. There's lots of space on the SSD and HDs.
Thanks for any suggestions!

System: Windows 7 Pro 64-bit; i7 2600k; 8G RAM; EVGA 260GTX; Intel SSD; HP SATA DVD writer.