I'm using Max 2019 (21.0-21.0.0.845) and the latest Substance Integration (can't seem to find version info) downloaded yesterday (5/13/18).
Every material that I apply to an object changes the size or scale of the object. If I disable 'Displacement' in the final Max material node it does not correct the issue. Setting 'Height Range' and 'Height Position' in the Substance will affect the size of the object but setting them to '0.00' does not return them to their normal sizes.
I've attached a screenshot. In the viewport i have the sphere just barely touching the surface and the edges of the 3 objects just barely tangent to each other. Also, in the torus, there is just a tiny slive showing in the middle.
In the render you can see that the scales have changed. The sphere is large and penetrates the surface. The box is larger and overlaps the sphere and the torus is smaller, exposing more in the center.
Anyone else having this issue? Maybe I'm overlooking a setting. Any suggestions?