Progress on Importing Model Correctly

At the moment my task is to make sure the model is imported from SketchUp to Unity correctly. To do this, I first turn the face style to monochrome in the View menu and checked the all the faces in SkecuUp Model to make sure there is no reversed faces.

After this step is the importing. I've tried several methods including export to .dae file directly from SketchUp. But the Unity dosen't seem to support the dae file directly exported by SketchUp well. There some faces displayed incorrectly in Unity but the the origin texture and color code are correct. Failed to find out the reason and fix the problem I've tried to use the Pro version of SketchUp to export the model into .fbx file. This time it works well. It s said that export into dae file by use the Playup plug-in also works well. I didn't have a go on that.

Exported .dae file

Exported .fbx file

Then I got another problem that the character can walk through walls. After researching and advice by Anthony, the solution to this is to explode everything in SketchUp model and make all of them one component. The switch on the COLLIDER in Unity. It works.