When you shared the model to the 3DW are you sure the box "Google Earth Ready: this 3D model is real, current and correctly-located." was checked? On your My Models page of the 3DW, there are options for All Models, Pending Google Earth Models etc. Which options does you model show up with?

This puzzles me a lot the model has hardly any geometry, i managed to get the file size down to 13.3MB thats all. That is a pretty big filem my latest model was only 12MB http://liam887.files.wordpress.com/2010/07/final-shot1.jpg and for this to be more is very puzzling! My best guess is that the textures you are using are much higher resolution than they need to be. Have you tried making them smaller and then re-saving your file and checking the size? Apart from this I have no idea I tried my usual tricks but only like you only got to 13.3? good luck and when you find out what was wrong let me know I would be interested to find out!!