I am filming the video, and wanted to make a list of the software issues to solve. For now I've had to do some workaround kluges to just show the idea in the video, but here is the to-do list to get around those:

• Right now I can write a command-line command to send an .svg to the printer at any time. Problems are:
  
  • Every time I issue the command, a new instance of the Inkscape GUI starts. Reading the forums, in my case I can't avoid starting the GUI but perhaps I can instantly kill it when it has done its job, which is marginally better than having many Inkscape instances accumulating.
  • Also I need to look at each of the several use-cases and figure out a way to generate .svg files. So, I'd take whatever data input I want (e.g. text from a webform, a drawing from an html5 canvas, weight readings from bluetooth bathroom scales, etc) and automatically generate an .svg, then call the draw command and delete the .svg. Or just skip the svg entirely.. but I'm just trying to solve one thing at a time here..
  • We will eventually need a queue where draw requests sit until the plotter is free to draw the next item.
• Because I'm building the mechanics of the next prototype from scratch, I won't be locked into Silhouette's (actually Graphtec's) firmware, which is a huge pain right now. So maybe I shouldn't spend too long wrestling with and unraveling the choices of some unknown firmware designers. I guess it depends how long we have until this thing is shipped to SPAAACE.. Jk ;)