Infill Issue

[MikeyDSG]

So I have a cylinder with a hollow center for a screw. The cylinder is about 1mm in diameter, as a result, it gets sliced to two inner rings, and two outer rings, but there's a gap in between, which I can not get infill to fill up. Even the top & bottom layers leave this ring open.. Cura slices it correctly, and I can't figure out what settings to use to make S3D give me a proper slice.. Yellow image is what Cura generates per layer, blue/cyan is S3D... help a newbie please!?

[S3D-Alex]

Could you post a Factory File so we can look into this and offer some advice? You can save this file by going to File > Save Factory File As...