The top image is my model after loading the STL
When I slice it, it looks like the bottom image
The cylinder should be hollow, but the bottom is now filled in.
The supports are shown for the top panels of the sides but the panels are missing
I have a Wanhao Duplicator i3, but I have tried slicing for different printers and I get the same result.
The STL came from Sketchup and from the top picture it looks good to me.
Any help to get a correct slice would be appreciated.