Blender version: 3.1.2
Plugin version: 3.2.1

When exporting a mesh the resulting SMD does not account for the unit of measurement used to create the mesh.

Tested by creating a meter cube and setting the unit system to Imperial. Resulting dimensions in the SMD are 0.5" in each direction from origin, whereas the dimensions should be 19.68504" in each direction. Manually changing unit scale to 39.37 and re-exporting had no effect.

Unknown if import process experiences same or similar issue.