I think you're just having 1st layer sticking issues. raise the bed so the 1st layer is flat on top.
Also are you using blue tape, or heated glass?
The STL looks fine and so does the gcode, you just need to get the bed adjusted and fix the sticking issue.
Also the brim is crazy huge, for an object like this I would change the brim to 3 or 4 in the expert settings, for some reason the default brim is 30.
Is the 0.4mm ring at the bottom in Cura? You are better to make the ring .41mm and then it will print fine. If it's a single wall thickness the same as the nozzle size the Cura won't print it. So if the .4 is at the bottom then it will only print the 0.8 mm which is higher up.
Always check layer View before you print anything.
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