I'm using Cura and it removes my holes and deletes sections of the print and disconnects parts. In Blender it looks as it should be, as I designed it. I know there are a few mishaps inside (not manifold) but is there a way to fill in everything on the inside. I only care about the externally facing faces. This is extremely infuriating I hope someone can tell me how to force Cura to print what is originally seen in the .stl.
These are photos of how it should look.
Now these next photos are how Cura previews it. Not only does it fill in the holes (no, fill holes isn't enabled) it adds huge gaps in the side and bottom of the print as can be seen.
How can I force Cura to print what I see in blender in the original .stl?
I am exporting in Blender to .stl and opening that in Cura.
I was able to fix it partially by fixing normals in Blender but there is still this: