Georeferencing with Scaleable Terrain Model in Descartes

I'm running into an issue with current DSMs being produced in ContextCapture and being displayed as Scaleable Terrain Models in Descartes.  Most recently I'm noticing that when I produce Orthos and DSMs in alternative SRSs, being a US projection in survey feet, the resultant SRS system for the DSM is not being honored in the Scalable Terrain Model workflow.  When I bring in the DSM and provide the correct coordinate system in the stm, I always get a scaled result that is converting the info straight back to metric, and not in the survey foot that I'm provided.  Coordinates too are being returned to metric.  Now the interesting thing to me is if I attach both the DSM and Ortho in Descarts as images they appear in the correct xy.  But the STM is not honoring the coordinate system, so I'm always off by the metric scale.  The design file settings are in english and working units are defined correctly.  This workflow has previously worked using the Update 17 ContextCapture and .74 Descarts, but now it doesn't. At this point I'm at a loss at what to do next and wondering if anyone else has encountered this ?