The company was named when the Nomad 883 Pro was the only product — the Shapeoko was added afterwards. Note that both machines use the same controller and the Shapeoko is capable of full 3D motion provided the correct toolpaths. You can check w/ the principals, @robgrz @Jorge and @edwardrford for further information on that.
If you wish, you could hand-code G-Code using a text editor: https://wiki.shapeoko.com/index.php/G-Code — this will afford total machine control.
Carbide Create is a 2.5D program, and is what is bundled with the Shapeoko, and what you started the discussion on.
Inkscape creates SVGs which import into Carbide Create fine, I believe GraviT will create files which will import as well. Cenon requires that one export PDFs, then use a second tool such as Inkscape to re-save as an SVG — they offer a CAM tool, but that’s a commercial option. If you have a file which locks up Carbide Create on import please send it in to us at email@example.com and we’ll try to have a developer look into it.
F-Engrave is a stand-alone CAM tool which makes toolpaths — it’s rather limited, but some folks find it quite useful (I used it to engrave the dial on my locking register calipers back before Carbide Create was available).
Please post a sample file, or send one in to firstname.lastname@example.org and we’ll do our best to work through this with you.