interesting I'll check that out. I used a stylus to draw over an old design. So everything is a stroke. I'll see if there's a way to group em up without it doing anything odd to the shapes. I use Affinity designer (and never really picked up Adobe illustrator so this side of design is new to me!)
I used Inkscape (https://inkscape.org/ ) - where you can just select all the paths that make up each shape and then tell it to Union them together into one. You can download my SVG file and compare the two. Makes it obvious if you select View ⇾ Display Mode ⇾ Outline Overlay