Export to STL causes slicing error.

[edcasati]

TRIED A DIFFFERENT SLICER. IT MIGHT WORK CORRECTLY.

I am having a problem where the STL generated by Fusion 360 appears to be correct, but is not.
If I select the root of a design, and do an "Export to STL" with the default option to create a single body, the output is one file, but in the places where some bodies intersect Fusion 360 generates what looks like a hollow area, not a joined area that one file should have.
The result is that when the object is 3D printed, it falls apart because there is nothing holding te items together in the problem area.

This image illustrates it clearly:

Bad slicing from STL

The problem seems to be in designs that have more than one component. The intersection between the components does not work, resulting in a hole when slicing.

I have tried everything, including flattening all the links, creating a new component that contains all the parts and exporting only that component, etc., to no avail.
Here is a slice of the file showing that the area is overlapped.

Section overlap between parts

I am attaching the STL output by Fusion, and the Fusion file that is giving me trouble.

Is the problem the way that I joined the two components in Fusion? 

I am out of things to try to get this file 3D printed correctly. Please help.

[edcasati]

I TRIED A DIFFERENT SLICER AND IT MIGHT WORK.

I will let you know.

[edcasati · Accepted solution]

(For the record)

The problem turned out to be that the Slicer needs a setting changed in order to correctly slice Fusion STL files, because Fusion STL files can have an error  that needs special attention by the slicer to fix. 

Slicer I was using is IdeaMaker by Raise3D. 

The setting needed is "Merge Internal Overlapping Parts" under Other tab in Advanced Settings.

The overlapping area that is being left open in error in the STL generated by Fusion needs to be corrected by the Slicer. Some Slicers do this automatically and some don't.