Simplify3D User Forum

I understood the version 4 can't allow anymore to set up the top and the bottom layer solid surface settings of each process.
Once all process of the model are merged, Simplify considers the model has one top and one bottom layer solid surface.

Is it possible to let the user an option to activate the function that each process has its own top and bottom layer solid surface settings?

Yes, you can still create solid layers between 2 processes if you need to. Just use the variable settings wizard to determine how big you want that region to be, then go to the Infill tab and enabled the "print solid diaphragm" option and set it to print every 1 layer. That will make that region completely solid.