The holes i made are instantly getting filled in the moment I lay the stl flat on the build plate

[BrodyMortensen360 0]

When i set the stl straight up the holes for the butterfly appear, but once I lay the stl flat the holes disappear and it becomes a flat sheet

Butterfly sheet topper try1.stl

[Slashee_the_Cow 269]

Before we get to settings: You have to make this thicker. Something one layer thick probably won't survive coming off the print bed. You don't need to change the model, just select your model, open the scale tool in Cura, turn off Uniform Scaling and increase the Z height to give it some thickness:

(Even 2mm is not really very thick, but I wouldn't even consider going below 1mm, pull out a ruler and you'll see).

 

Okay, on to settings (you might have to make all settings visible or search for some of these):

• Quality > Line Width to whatever the narrowest you can pull off is. Most printers come with a 0.4mm nozzle and I find I can go down to a line width of 0.26mm reliably with that.
• Quality > Initial Layer Line Width to 100%. I think that's the default, but you should just double check.
• Okay, now the one that actually matters: Experimental > Slicing Tolerance to Exclusive. That guarantees that Cura will always round in favour of making holes to match a model.

With all of those, you get this:

[BrodyMortensen360 0]

Oh my goodness that is so so so helpful!!! Thank you so much!!!!