1. "locked to lissence" means you can load/import it into vue but you cant export it from vue. So for example, if you bought a model of a car you can get it into vue but you cant export it in an 'obj' format to be used in another  application. It can be a bit annoying if you want to make some modifications to the model - you cant do it in vue and you cant get it into a modelling program. The locked versions are cheaper though - so its up to you what you buy.
   You can install it anywhere you like, but if it isnt in the forlder vue expects it you will need to add your folder when you load the first time.
2. That's odd. When I click on 'vehicles' and then 'space' I get 26 items displayed. The other sub-tabs also display items for me.

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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