This issue is related only to "Advanced Material" option in Viewport preferences > Settings (first tab) > Material Rendering Level.
There is non-transparent material applied to the blue object and the expected result is to not see anything through it. Changing this option to default "Material Editor Setting" or "Basic Material" fixes everything.
And this is a 3ds Max glitch rather than anything related to Corona.
Hello Aram,
Thank you and the support team for promptly investigating my two scenes.
Indeed, this is different issue.
To be honest, changing the material rendering level in the viewport settings is just one of three possible ways to restore normal viewport behavior.
It is not yet clear whether changing the Material Rendering Level from "advanced" to "basic" permanently helps, as an second option we can also simply switch the Viewport Display Mode to "performance" and then back to "standard" and achieve the same result.
And the third way is to disable transparency in the viewport settings.
Have you noticed all three of these methods?
It's interesting that this bug persists even in newer versions of 3ds Max, such as 2023 and 2024. I will report it to Autodesk.
Best regards