How to open .3Ds files to use them in SketchUp?
If you want to use in SketchUp a plan exported from Visuary in .3Ds format, please note that it cannot be opened directly.
First, the .3Ds export is automatically downloaded as a compressed file (.zip). You must start by extracting this file.
Then, open SketchUp and choose the Import a file option, not Open a file.