Problem unloading to Shapeways

I’ll have a go. I’m pretty new to this, but your tutorial videos have been so encouraging. I may have tried to run before I could walk so feel free to be honest with your assessment. If you think I should go back and start from scratch then please do tell me. I have found your software a joy to work with and much more intuitive and versatile than other platforms I experimented with. Best wishes, ANW