Experimental Spaghetti infill produces strange preview

[StarNamer 4]

Having noticed that CURA 4.5 was available, I read the release notes and was interested to see what effect Spaghetti Infill had. I tried it on an STL file I happened to have (Z rod knob for Ender 3 -  http://www.thingiverse.com/thing:3568572) and got a very strange preview at layer 25:

The profile I was using was the default Low Quality with the following changes:

  Infill Density: 40%

  Print Speed: `130mm/s

  Initial Layer Speed: 40mm/s

  Support Placement: Touching Buildplate (but Generate Support is off)

  Tree Support: On

  Spaghetti Infill: On

 

There doesn't seem to be anything odd about the GCode and it looks fine when loaded:

 

Of course, when looking at the infill, it's not clear what would happen as the Cubic infill is missing several layers and would, I expect, become spaghetti! Perhaps that's what's intended?

 

CE3_Z_Knob_apl - spaghetti error.gcode

Edited April 7, 2020 by StarNamer