Hello Steve,
I’ve been using Zappar for a while now for various projects and always have success with models. Today I was having trouble importing an fbx with UV/imagemap as I usually do but from a PC. A bit puzzled, I thought I’d create a simple cube, uv and texture it. Dragging it into Zappar there are no errors but the model isn’t visible in the preview window although it was still asking for me to drop the jpg image map in. Everything went into Zappar, dragged it onto the main stage and nothing.
A little puzzled. While writing this reply, I’m now wondering if the actual scale of an object can cause a problem (only thing I haven’t checked) as everything else is how I do things as usual.