not sure about the driver, I'm thinking the washers must be drawn in 4 quadrants with a node at each 'corner'-?
If so, then these other problems (I've highlighted)--
misalgn.jpg
may be due to the source material, OR, your engraving program's inability to "deal" with it...
As my reference: If I load this graphic, shown painted and wireframe, which works perfectly fine in Corel-
spd1.jpg
Into my Chinese Triumph's 8 year old engraving program (Lasersoft),
it works perfectly--or I should say 'paints' perfectly--
mis2.jpg
Yes I'm rastering and not cutting, but I'm not thinking that matters here...
However, If I load the same exact graphic into just a year-newer version of
Lasersoft, I get this nonsense...
mis3.jpg
And it will engrave just like this--
But this version of Lasersoft has a 'locate data errors' function the early version doesn't.
When checking for errors, the program finds dozens of them!
mis4.jpg
Good hell, 22 sections unclosed, 66 overlaps, 14 intersections and 10 collisions-!
What's it all mean? Not sure but none of these errors are 'findable' in Corel, and even though the Lasersoft error function is supposed to be able to fix the errors, it simply doesn't work... I've tried many newer versions of Lasersoft, I found one that actually works pretty good but, and I don't remember what exactly it did, but it did something screwy and I stopped using it, and went back to the version I've been using...
and yet, this riddled-with-errors spade works fine otherwise...?
That all said, this is why I think the problem may be your source material, in one way or another... Lately I've been getting graphics created in Adobe Illustrator, and I'm appalled at how AI, while making it easy for designers to draw things that print out on banners and paper just dandy, makes life for those running XY plotting machines a living nightmare... I've gotten graphics with over 20 different layers of stacked graphics; if the designer needs another color he just draws a new shape and stacks it on top of another shape. While a printer only sees the surface colors, a plotter will see every last thing in the design. Newer laser software may be able to ignore the lower layers, but mine don't, and especially not my Chinese software...