Apologies for the delay, as I was out sick... The solution was found in another helpful PowerPoint presentation supplied by John at PTC, again, and was as simple as remodeling the holes as simple cylinders. Seems Wildfire cannot yet handle chamfers, or threaded surfaces, or pre-drills or countersinks, or counterbores. Once the model was simplified, the pre-tension worked just as anticipated. John, had some additional advice in his reply copied below. Additionally, Todd sent me a nice PDF document "Understanding Pre-load and Tensile Force in Advanced Fasteners" of just how Wildfire treats it's fastener function. Some of this is repetitive information from the PTC Help Topic CD, but has plenty of very informative content. It is unclear where this originated, so hopefully I'm not offending anyone by distributing it to those who ask. I will be happy to supply both documents to those who request them.