Painted Object with Modifier object

[Mr.Exocomp]

I have an object that I imported as an OBJ, and painted several pieces of it in BS. I wanted a portion of the object to have a higher infill percentage. When I added a Object Modifier club to cover that area and set its infill higher (80%). it didl not work when sliced. the entire object was still the lower infill % (10%)

[JayZay]

I just imported an .obj file, painted, add a modifier for 50% infill:

And it works:

Can you share further details about your model and modifier?