#119 g-step and g-stl changing subtraction to union

[Forrest McKee]

Hello,
I'm working on a problem where i'm given a step file from Solid Works, use step-g to open it in BRL-CAD, create a hole pattern of RCC's, and then subtracting those RCC's from the single Region in BRL-CAD. When I try and convert the file back to a step or stl (because they work in Solid Works) my hole pattern is changed from a subtraction to a union. So I have a model with rods protruding from it rather than a model with holes in it. I'm getting tessellation errors when I try to use g-stl.
Is this a bug in the app to convert between files or user-error?

Thank you!