No, i not install it with dragging to construct, i create folder ini exporter/html5/behavior, and i put file with [plugin] name in plugin folder. btw i download Baby 3D Plugins and Behaviors (0.91).zip file, and and the contents of the zip folder are this
Viewing post in How to use B3D Model Plugin
Your issue doesn't appear to be related to the Model plugin preview after all.
To properly install Baby 3D with all its parts you should unzip the archive you downloaded. Then open Construct 2 and drag each file with a c2addon extension into the C2 window. This will prompt you to install the addons.
Also remove any plugin or behavior folders you may have created manually first.
If the issue persists please create a new topic or contact me directly.