No, you can't download Outerra anywhere. The sites you mention create links to trojans named automatically by the query you enter when searching for software, so basically it's you who makes it to
exist on those sites. If you search today for Outerra Universe Simulator, in few days there will be a link asserting they've got a high speed download of OUS.
We don't know yet when the engine will be released; moreover I guess you want a vehicle sim and not an engine - and that's even more unclear.
There's no mud/soft ground yet, but we'll be implementing it to demo the possibility in engine - but mostly from the rendering point of view, as we aren't making a vehicle simulator now.
I've already replied to your flex* questions in
another post.
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RoR limits the number of view angles somehow? A game can use how many it wants.