Hi John & Wo3Dan,
Thanks for your comments.
I've copied the model by Command + A and paste it in a new file which gave me the same problems.
Yes, I have tried anything from the Zoom Extents and Clipping Plane. But didn't work for me.
I started with an older sketch up file after posting this topic, copied parts out of the newer model when possible (soon I used Orbit I lost my model). I noticed when I added a third or more Text labels to the model, that's where the trouble started.
I will try deleting the text labels. Hopefully it won't get weird again with the orbit tool and not making adjustments to the model.
Otherwise I will upload the model for an another look.
Keep you posted!