Shapeways Renders, How Do They Work?

My products are mostly just for plain white nylon prints, particularly after the price increases for dyed products. Anyway, that's why I always used the Shapeways render that appears on a product page before you define any materials for sale. It looks better than a white plastic render and makes more sense for mechanical oriented products. I want to highlight the functionality (edges, curves, pivot points, joints, etc.). At first it worked great but at some point the images no longer always fit into the frame of the photo. Now sometimes they do, sometimes they don't.

What I'm trying to figure out is what is setting the image limits. I uploaded several variations of a model and sometimes things got better but everything doesn't always gets stuffed into the view. Maybe I'd be better off using an external program to generate a render but that's more work and less consistent than just using a Shapeways generated image method that I started with.

Here's the image from one example product.


Not so great. Then I tried editing the file in various ways and uploading the modified files just to get improved images that I could upload to the original product page. But they all suffer from similar problems of missing model portions. (The 90 degree rotation around the z-axis worked best.) So the question is, is there workaround for the model upload that gets the whole thing into the image frame? Is this a known bug that might get fixed. Any other suggestions?

Original product.
https://www.shapeways.com/product/K3VW7WTAZ/aquarium-ground-anchor-2-inch-disk-x2

Here are some of the other file upload attempts.
https://www.shapeways.com/product/FDG3P8RJW/image-test-50-percent-scale

https://www.shapeways.com/product/R5US37CJN/image-test-90-degree-rotation

https://www.shapeways.com/product/9MH2E8H4M/image-test-90-degree-forward-flip

I tried some other things to upload for a decent product image. I think the basic problem is that the system doesn't scale and center images properly. Note that this problem also exists in the My 3D Models listing images. The same images are used there if you don't create a product and that makes it hard to navigate to find a specific model if you are scanning the images.

Here's another product with a messed up render:



To try and get a better image I then uploaded this model with extra cubes added above and below the model:



Once creating a product for this new part an acceptable render was finally obtained, although it's still not centered left to right:



Quite a pain in the butt this is.

It appears that this issue has been fixed. I've uploaded a few models and the renders are now nicely centered within the image boundaries.