We have added ‘bake preview’ in July, which allows for real-time lighting preview. Check this out:
You can already take screenshots in Shapespark by pressing ‘P’. You can take screenshots in both editor and viewer, but editor gives you more control. You can even take panorama screenshots.
If you want to be able to make a high-quality renders in Shapespark, then this is on our roadmap just like automatic bump map creation and we will consider adding those features to Shapespark next year.