Hi @Anonymous
Thanks for posting! Is the odd configuration you mentioned pictured in your screenshot? I can see that the "add or remove brep/t-spline bodies" message in the screenshot, which suggests that the mouse cursor is hovering over the body you have already selected - which will change the shading you see. If this is not the weird behavior you are describing, it may help to create a screencast illustrating what you are seeing - I am happy to have a look!
As for the lack of difference between 99% and 100% opacities, I believe this is working is intended. I don't think my eyes are sharp enough to see any difference when changing the opacity by one - I tested 99/100%, 49/50/51%, and some other numbers - I think the change made by adding or subtracting one point is simply too small a change to visually distinguish. This is why the slider is used for the opacity field rather than a specific numerical input - it allows us to not worry about precision and simply pull to a place that looks good.
Hopefully this helps! Please let me know if you have any questions.
Paul Clauss
Product Support Specialist