Your comments

Origami got camera properties window where you can set that.
Looks like we've done everything except for the curve crease lines, but there is a separate suggestion for that. Closing this one for now.
Doesn't it help to choose PDF version while saving imposed documents? Its like you make a new PDF file - you don't choose it version until you save it.
Done in version 1.3, simply drag material onto another one, hold it for a second while the other material gets selected and release the mouse. This will replace the material with the one you dragged and update all the meshes using it.
Done in version 1.3
We've added watermark option in version 1.3, please feel free to mention Olwet in your watermarks, as well :)
We have no plans on releasing just a rendering part of Owlet because there is no 100% working way to match Boxshot materials to the Owlet ones. On the other hand, we reduced Owlet price to the level where you can probably afford the whole application instead of just renderer.
So instead of tinting whites, you want to tint blacks. Got it, will think about this, thank you.
Actually tint does exactly what you describe. Internally we multiply texture color by tint, so having gray texture with yellow tint gives you dark yellow color. If you need something else, please provide a small before/after example, so I can understand you better.
Any chance you can provide slightly more details with your request, please? Like a sample PDF with all the features you need? Thank you.