Is there a way to remove inner areas?

[asdronin]

Hi all, 

I saw here that there is this great method to convert from LDD to the obj file merging many hidded parts and making it a lot more game friendly but still in some complex models I cant cover all the bottom areas to make the inner areas vanish, so isnt there a converter that aside from merging and delete hidden parts could delete all the inner areas? I know this way the model could look less Lego as some back parts will look flat opposed to the regular Lego inner areas but for a game it would be a lot better, so I wonder if this can be done. Sinc eIm new I hope I posted this in the right place, if not please receive my apologies and move this to where it should be