What happens with failed assertions?

Unfortunately with Customizer you can’t limit the range of a user input based on another user input. For example, a script could ask for a number of elements and a size of those elements whereby numbersize has to not exceed the width of the model. A solution is an assert statement like: assert(countsize <= width, “There isn’t enough room for all the elements.”);

When an assertion fails how does that manifest in Model’s UI?

Yes. This is an excellent idea. Today we release a major upgrade to other both the backend and the front end that support including a ZIP file with modules, fonts, CAD file with your model.

I will add this topic to the list of customizer enhancements we will consider in the future.

Fortunately, the customizer at Models @ MakeWithTech is not limited to the current OpenSCAD spec. As long was we generate valid OpenSCAD script we can make our customizer much more sophisticated.

@dbarthel Here is a public link to the Models @ MakeWithTech backlog. Feel free to share this with others.